CVE-2026-68155

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-68155", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.371Z", "datePublished": "2026-08-10T11:59:21.200Z", "dateUpdated": "2026-10-19T20:58:54.643Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-03T10:55:38.556Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Reject monmaps advertising zero monitors\n\nA message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a\nmonitor to the client. This monmap contains information about the\nexisting monitors in the cluster. Currently, a monmap indicating that\nthere are zero monitors in the cluster is treated as valid. However, it\nis impossible to have zero monitors in the cluster and still receive a\nvalid monmap from a monitor. Therefore, such a monmap must be corrupted\nand should be treated as invalid. Furthermore, a monmap with a monitor\ncount of zero can subsequently crash the client when attempting to open\na session with a monitor in __open_session(). This happens because the\n\"BUG_ON(monc->monmap->num_mon < 1)\" assertion in pick_new_mon() is\ntriggered.\n\nThis patch extends a check in ceph_monmap_decode() to also reject\narriving mon_maps with num_mon == 0 rather than only with\nnum_mon > CEPH_MAX_MON.\n\n[ idryomov: drop \"log output for unusual values of num_mon\" part ]"}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:N - The bug is reached when libceph decodes CEPH_MSG_MON_MAP from a remote Ceph monitor over the kernel client's established TCP/msgr2 session (mon_dispatch -> ceph_monc_handle_map -> ceph_monmap_decode), which is a network protocol attack surface on CephFS/RBD/cloud nodes.\nAC:L - An attacker who can send monitor protocol messages only needs to set num_mon=0 in the monmap; once accepted, any later session reopen (keepalive timeout, hunt, or connection fault) deterministically hits BUG_ON in pick_new_mon without races or special memory layout.\nPR:N - In the highest-impact scenario a malicious or compromised Ceph monitor (or equivalent authenticated cluster peer) sends the malformed monmap to already-connected kernel clients; the attacker needs no local privileges on the victim host.\nUI:N - After a Ceph client session exists, monmap updates are delivered and processed automatically by the kernel monitor client; no further mount, open, or other victim interaction is required to accept the bad map and later crash on reconnect.\nS:U - Exploitation causes a kernel BUG/panic within the same kernel security domain and does not cross VM, container, IOMMU, or other security boundaries.\nC:N - The failure mode is a BUG_ON assertion in pick_new_mon when num_mon is zero; there is no memory corruption, out-of-bounds access, or other information disclosure primitive on the vulnerable path.\nI:N - Accepting num_mon==0 only stores an empty monmap and later triggers a deliberate kernel BUG; attacker input does not corrupt or modify arbitrary kernel memory or enable code execution.\nA:H - BUG_ON(monc->monmap->num_mon < 1) in pick_new_mon during __open_session causes a kernel oops/panic, fully denying availability of the affected host until reboot."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ceph/mon_client.c"], "versions": [{"version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "ba5f0015bfd376d764163045a61c17be75f44dae", "status": "affected", "versionType": "git"}, {"version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "caf082ef8609a6ac26159ce115f55ab7d00231a3", "status": "affected", "versionType": "git"}, {"version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "e3ccd4ecab09b22f507f49cb7ed9990c7158ceab", "status": "affected", "versionType": "git"}, 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"2.6.34", "status": "affected"}, {"version": "0", "lessThan": "2.6.34", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.148", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.101", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.42", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "5.10.271"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "5.15.216"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.1.183"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.6.148"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.12.101"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "6.18.42"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "7.1.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.34", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/ba5f0015bfd376d764163045a61c17be75f44dae"}, {"url": "https://git.kernel.org/stable/c/caf082ef8609a6ac26159ce115f55ab7d00231a3"}, {"url": "https://git.kernel.org/stable/c/e3ccd4ecab09b22f507f49cb7ed9990c7158ceab"}, {"url": "https://git.kernel.org/stable/c/0591a15815b498be628a937146e44487d599ba33"}, {"url": "https://git.kernel.org/stable/c/cd0d41bc569632eaaeccde9d2a6bc919ec00c407"}, {"url": "https://git.kernel.org/stable/c/e67e8b694872c9bc66996040f9de9242f6236ed9"}, {"url": "https://git.kernel.org/stable/c/3b249546f59c3d6d3592c10657f82bc3f1faa07c"}, {"url": "https://git.kernel.org/stable/c/40480eee361ed9676b3f844d532ac28b47251634"}], "title": "libceph: Reject monmaps advertising zero monitors", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-68155", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-10-16T15:45:06.305922Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-20", "description": "CWE-20 Improper Input Validation"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-19T20:58:54.643Z"}}]}}

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once accepted, any later session reopen (keepalive timeout, hunt, or connection fault) deterministically hits BUG_ON in pick_new_mon without races or special memory layout.\nPR:N - In the highest-impact scenario a malicious or compromised Ceph monitor (or equivalent authenticated cluster peer) sends the malformed monmap to already-connected kernel clients; the attacker needs no local privileges on the victim host.\nUI:N - After a Ceph client session exists, monmap updates are delivered and processed automatically by the kernel monitor client; no further mount, open, or other victim interaction is required to accept the bad map and later crash on reconnect.\nS:U - Exploitation causes a kernel BUG/panic within the same kernel security domain and does not cross VM, container, IOMMU, or other security boundaries.\nC:N - The failure mode is a BUG_ON assertion in pick_new_mon when num_mon is zero; there is no memory corruption, out-of-bounds access, or other information disclosure primitive on the vulnerable path.\nI:N - Accepting num_mon==0 only stores an empty monmap and later triggers a deliberate kernel BUG; attacker input does not corrupt or modify arbitrary kernel memory or enable code execution.\nA:H - BUG_ON(monc->monmap->num_mon < 1) in pick_new_mon during __open_session causes a kernel oops/panic, fully denying availability of the affected host until reboot."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "ba5f0015bfd376d764163045a61c17be75f44dae", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "caf082ef8609a6ac26159ce115f55ab7d00231a3", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "e3ccd4ecab09b22f507f49cb7ed9990c7158ceab", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "0591a15815b498be628a937146e44487d599ba33", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "cd0d41bc569632eaaeccde9d2a6bc919ec00c407", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "e67e8b694872c9bc66996040f9de9242f6236ed9", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "3b249546f59c3d6d3592c10657f82bc3f1faa07c", "versionType": "git"}, {"status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "lessThan": "40480eee361ed9676b3f844d532ac28b47251634", "versionType": "git"}], "programFiles": ["net/ceph/mon_client.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "2.6.34"}, {"status": "unaffected", "version": "0", "lessThan": "2.6.34", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.271", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.216", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.183", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.148", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.101", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.42", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.1.6", "versionType": "semver", "lessThanOrEqual": "7.1.*"}, {"status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/ceph/mon_client.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/ba5f0015bfd376d764163045a61c17be75f44dae"}, {"url": "https://git.kernel.org/stable/c/caf082ef8609a6ac26159ce115f55ab7d00231a3"}, {"url": "https://git.kernel.org/stable/c/e3ccd4ecab09b22f507f49cb7ed9990c7158ceab"}, {"url": "https://git.kernel.org/stable/c/0591a15815b498be628a937146e44487d599ba33"}, {"url": "https://git.kernel.org/stable/c/cd0d41bc569632eaaeccde9d2a6bc919ec00c407"}, {"url": "https://git.kernel.org/stable/c/e67e8b694872c9bc66996040f9de9242f6236ed9"}, {"url": "https://git.kernel.org/stable/c/3b249546f59c3d6d3592c10657f82bc3f1faa07c"}, {"url": "https://git.kernel.org/stable/c/40480eee361ed9676b3f844d532ac28b47251634"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Reject monmaps advertising zero monitors\n\nA message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a\nmonitor to the client. This monmap contains information about the\nexisting monitors in the cluster. Currently, a monmap indicating that\nthere are zero monitors in the cluster is treated as valid. However, it\nis impossible to have zero monitors in the cluster and still receive a\nvalid monmap from a monitor. Therefore, such a monmap must be corrupted\nand should be treated as invalid. Furthermore, a monmap with a monitor\ncount of zero can subsequently crash the client when attempting to open\na session with a monitor in __open_session(). This happens because the\n\"BUG_ON(monc->monmap->num_mon < 1)\" assertion in pick_new_mon() is\ntriggered.\n\nThis patch extends a check in ceph_monmap_decode() to also reject\narriving mon_maps with num_mon == 0 rather than only with\nnum_mon > CEPH_MAX_MON.\n\n[ idryomov: drop \"log output for unusual values of num_mon\" part ]"}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.271", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15.216", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.183", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.148", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.101", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.42", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.1.6", "versionStartIncluding": "2.6.34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.2", "versionStartIncluding": "2.6.34"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-03T10:55:38.556Z"}}}, "cveMetadata": {"cveId": "CVE-2026-68155", "state": "PUBLISHED", "dateUpdated": "2026-10-19T20:58:54.643Z", "dateReserved": "2026-07-30T09:28:09.371Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-08-10T11:59:21.200Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/ceph/mon_client.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "ba5f0015bfd376d764163045a61c17be75f44dae", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "caf082ef8609a6ac26159ce115f55ab7d00231a3", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "e3ccd4ecab09b22f507f49cb7ed9990c7158ceab", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "0591a15815b498be628a937146e44487d599ba33", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "cd0d41bc569632eaaeccde9d2a6bc919ec00c407", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "e67e8b694872c9bc66996040f9de9242f6236ed9", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "3b249546f59c3d6d3592c10657f82bc3f1faa07c", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}, {"lessThan": "40480eee361ed9676b3f844d532ac28b47251634", "status": "affected", "version": "ba75bb98cfb93b62c54af25bf67ff90857264bbe", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/ceph/mon_client.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.34"}, {"lessThan": "2.6.34", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.271", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.216", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.183", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.148", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.101", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.42", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Reject monmaps advertising zero monitors\n\nA message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a\nmonitor to the client. This monmap contains information about the\nexisting monitors in the cluster. Currently, a monmap indicating that\nthere are zero monitors in the cluster is treated as valid. However, it\nis impossible to have zero monitors in the cluster and still receive a\nvalid monmap from a monitor. Therefore, such a monmap must be corrupted\nand should be treated as invalid. Furthermore, a monmap with a monitor\ncount of zero can subsequently crash the client when attempting to open\na session with a monitor in __open_session(). This happens because the\n\"BUG_ON(monc->monmap->num_mon < 1)\" assertion in pick_new_mon() is\ntriggered.\n\nThis patch extends a check in ceph_monmap_decode() to also reject\narriving mon_maps with num_mon == 0 rather than only with\nnum_mon > CEPH_MAX_MON.\n\n[ idryomov: drop \"log output for unusual values of num_mon\" part ]"}], "id": "CVE-2026-68155", "lastModified": "2026-10-19T21:17:55.503", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-68155", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:45:06.305922Z", "version": "2.0.3"}}]}, "published": "2026-08-10T13:20:01.657", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0591a15815b498be628a937146e44487d599ba33"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3b249546f59c3d6d3592c10657f82bc3f1faa07c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/40480eee361ed9676b3f844d532ac28b47251634"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ba5f0015bfd376d764163045a61c17be75f44dae"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/caf082ef8609a6ac26159ce115f55ab7d00231a3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/cd0d41bc569632eaaeccde9d2a6bc919ec00c407"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e3ccd4ecab09b22f507f49cb7ed9990c7158ceab"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e67e8b694872c9bc66996040f9de9242f6236ed9"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-20"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: Linux kernel (libceph): Denial of Service due to malformed monitor maps", "id": "2513295", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2513295"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-617", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nlibceph: Reject monmaps advertising zero monitors\nA message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a\nmonitor to the client. This monmap contains information about the\nexisting monitors in the cluster. Currently, a monmap indicating that\nthere are zero monitors in the cluster is treated as valid. However, it\nis impossible to have zero monitors in the cluster and still receive a\nvalid monmap from a monitor. Therefore, such a monmap must be corrupted\nand should be treated as invalid. Furthermore, a monmap with a monitor\ncount of zero can subsequently crash the client when attempting to open\na session with a monitor in __open_session(). This happens because the\n\"BUG_ON(monc->monmap->num_mon < 1)\" assertion in pick_new_mon() is\ntriggered.\nThis patch extends a check in ceph_monmap_decode() to also reject\narriving mon_maps with num_mon == 0 rather than only with\nnum_mon > CEPH_MAX_MON.\n[ idryomov: drop \"log output for unusual values of num_mon\" part ]", "A flaw was found in the libceph component of the Linux kernel. A remote attacker could send a specially crafted monitor map (monmap) that advertises zero monitors. This malformed monmap is incorrectly processed as valid, which can lead to a client crash when attempting to open a session. This vulnerability results in a Denial of Service (DoS) for the client."], "name": "CVE-2026-68155", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:enterprise_linux_nvidia:", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux for NVIDIA 26"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-08-10T11:59:21Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-68155\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-68155\nhttps://git.kernel.org/stable/c/0591a15815b498be628a937146e44487d599ba33\nhttps://git.kernel.org/stable/c/3b249546f59c3d6d3592c10657f82bc3f1faa07c\nhttps://git.kernel.org/stable/c/40480eee361ed9676b3f844d532ac28b47251634\nhttps://git.kernel.org/stable/c/cd0d41bc569632eaaeccde9d2a6bc919ec00c407\nhttps://git.kernel.org/stable/c/e67e8b694872c9bc66996040f9de9242f6236ed9"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,0591a15815b498be628a937146e44487d599ba33)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,cd0d41bc569632eaaeccde9d2a6bc919ec00c407)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,e67e8b694872c9bc66996040f9de9242f6236ed9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,3b249546f59c3d6d3592c10657f82bc3f1faa07c)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,40480eee361ed9676b3f844d532ac28b47251634)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.6.148)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.12.101)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.18.42)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,7.1.6)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.6.148,6.6.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.12.101,6.12.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[6.18.42,6.18.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1.6,7.1.*]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-rc5,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-10T16:15:04.170399+00:00", "updated": "2026-10-20T10:30:06.313210+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}