CVE-2026-99126

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-99126", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.393Z", "datePublished": "2026-10-28T10:34:40.661Z", "dateUpdated": "2026-10-30T12:41:59.971Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:41:59.971Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ns390/ctcm: Prevent XID null dereference\n\nThe mpc_validate_xid() function sets grp->saved_xid2->xid2_flag2 to 0x40\nto signal XID validation error. If peer XID is NULL or r/w channel\npairing mismatch happens, grp->saved_xid2 is never initialized. An\nattempt to set the flag in such case leads to NULL dereference.\n\nFix this by using the always available priv->xid->xid2_flag2 instead of\ngrp->saved_xid2->xid2_flag2 for validation errors."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/s390/net/ctcm_mpc.c"], "versions": [{"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "f9d9e2dadc9fbdfe01aeb6581978c3b59092919e", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "a7c3e1795e4fe5e6680cab7cd7eee0503b00a248", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "c11e435d334e4c311eaaf721e179a5ca6852c221", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "977dac6cc5531a8e058df05b6af94406b940cb9e", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "1525fb6e2f9f9a2c8c8723ee0959b1130a6b8213", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "34fa3607b7604b3052b19cec8b0ad644818cdd2a", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab", "status": "affected", "versionType": "git"}, {"version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "lessThan": "b264d8422779d69febce914efc47a92a85cc382c", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["drivers/s390/net/ctcm_mpc.c"], "versions": [{"version": "2.6.26", "status": "affected"}, {"version": "0", "lessThan": "2.6.26", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.273", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.224", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.161", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.115", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.59", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.13", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "2.6.26", "versionEndExcluding": "5.10.273"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "5.15.224"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.6.161"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.12.115"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "6.18.59"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "7.2.13"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.26", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/f9d9e2dadc9fbdfe01aeb6581978c3b59092919e"}, {"url": "https://git.kernel.org/stable/c/a7c3e1795e4fe5e6680cab7cd7eee0503b00a248"}, {"url": "https://git.kernel.org/stable/c/c11e435d334e4c311eaaf721e179a5ca6852c221"}, {"url": "https://git.kernel.org/stable/c/977dac6cc5531a8e058df05b6af94406b940cb9e"}, {"url": "https://git.kernel.org/stable/c/1525fb6e2f9f9a2c8c8723ee0959b1130a6b8213"}, {"url": "https://git.kernel.org/stable/c/34fa3607b7604b3052b19cec8b0ad644818cdd2a"}, {"url": "https://git.kernel.org/stable/c/8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab"}, {"url": "https://git.kernel.org/stable/c/b264d8422779d69febce914efc47a92a85cc382c"}], "title": "s390/ctcm: Prevent XID null dereference", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["drivers/s390/net/ctcm_mpc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "f9d9e2dadc9fbdfe01aeb6581978c3b59092919e", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "a7c3e1795e4fe5e6680cab7cd7eee0503b00a248", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "c11e435d334e4c311eaaf721e179a5ca6852c221", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "977dac6cc5531a8e058df05b6af94406b940cb9e", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "1525fb6e2f9f9a2c8c8723ee0959b1130a6b8213", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "34fa3607b7604b3052b19cec8b0ad644818cdd2a", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}, {"lessThan": "b264d8422779d69febce914efc47a92a85cc382c", "status": "affected", "version": "293d984f0e3604c04dcdbf00117ddc1e5d4b1909", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["drivers/s390/net/ctcm_mpc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.26"}, {"lessThan": "2.6.26", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.273", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.224", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.161", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.115", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.59", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.13", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "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\ns390/ctcm: Prevent XID null dereference\n\nThe mpc_validate_xid() function sets grp->saved_xid2->xid2_flag2 to 0x40\nto signal XID validation error. If peer XID is NULL or r/w channel\npairing mismatch happens, grp->saved_xid2 is never initialized. An\nattempt to set the flag in such case leads to NULL dereference.\n\nFix this by using the always available priv->xid->xid2_flag2 instead of\ngrp->saved_xid2->xid2_flag2 for validation errors."}], "id": "CVE-2026-99126", "lastModified": "2026-10-30T13:21:46.747", "metrics": {}, "published": "2026-10-28T11:17:32.317", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1525fb6e2f9f9a2c8c8723ee0959b1130a6b8213"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/34fa3607b7604b3052b19cec8b0ad644818cdd2a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/977dac6cc5531a8e058df05b6af94406b940cb9e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a7c3e1795e4fe5e6680cab7cd7eee0503b00a248"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b264d8422779d69febce914efc47a92a85cc382c"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c11e435d334e4c311eaaf721e179a5ca6852c221"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f9d9e2dadc9fbdfe01aeb6581978c3b59092919e"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: kernel: Denial of service via null pointer dereference in s390/ctcm", "id": "2562658", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2562658"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\ns390/ctcm: Prevent XID null dereference\nThe mpc_validate_xid() function sets grp->saved_xid2->xid2_flag2 to 0x40\nto signal XID validation error. If peer XID is NULL or r/w channel\npairing mismatch happens, grp->saved_xid2 is never initialized. An\nattempt to set the flag in such case leads to NULL dereference.\nFix this by using the always available priv->xid->xid2_flag2 instead of\ngrp->saved_xid2->xid2_flag2 for validation errors.", "A flaw was found in the Linux kernel's s390 CTCM (Channel-to-Channel) driver. A denial of service (DoS) can occur when the driver processes invalid Exchange Station Identification (XID) data during channel negotiation. If a peer XID is missing or a channel pairing mismatch occurs, the driver attempts to record a validation error on an uninitialized data structure, triggering a null pointer dereference. This flaw allows a peer or attacker to cause a kernel crash."], "name": "CVE-2026-99126", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Not affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-10-28T10:34:40Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-99126\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-99126\nhttps://git.kernel.org/stable/c/34fa3607b7604b3052b19cec8b0ad644818cdd2a\nhttps://git.kernel.org/stable/c/8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab\nhttps://git.kernel.org/stable/c/b264d8422779d69febce914efc47a92a85cc382c"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[293d984f0e3604c04dcdbf00117ddc1e5d4b1909,34fa3607b7604b3052b19cec8b0ad644818cdd2a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[293d984f0e3604c04dcdbf00117ddc1e5d4b1909,8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[293d984f0e3604c04dcdbf00117ddc1e5d4b1909,b264d8422779d69febce914efc47a92a85cc382c)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "2.6.26"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,2.6.26)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.59,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.13,8.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[293d984f0e3604c04dcdbf00117ddc1e5d4b1909,34fa3607b7604b3052b19cec8b0ad644818cdd2a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[293d984f0e3604c04dcdbf00117ddc1e5d4b1909,8a2f7a4ad1d81612fa65bfa4d392ba1bb2f5eeab)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[293d984f0e3604c04dcdbf00117ddc1e5d4b1909,b264d8422779d69febce914efc47a92a85cc382c)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "2.6.26"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,2.6.26)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.59,7.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.13,8.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-10-28T12:45:16.182084+00:00", "updated": "2026-10-30T03:00:13.076295+00:00", "vendors": ["linux", "linux$PRODUCT$linux", "linux$PRODUCT$linux_kernel"]}