CVE-2026-99139

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-99139", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:25:14.395Z", "datePublished": "2026-10-28T10:34:50.674Z", "dateUpdated": "2026-10-30T12:42:11.824Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:42:11.824Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION)\n\ndo_tcp_getsockopt() reads icsk->icsk_ca_ops->name without holding\nrcu_read_lock(). Since commit 0baf26b0fcd7 (\"bpf: tcp: Support\ntcp_congestion_ops in bpf\"), icsk_ca_ops can point to dynamically\nallocated BPF struct_ops memory that may be freed concurrently via\nsetsockopt(TCP_CONGESTION), leading to a use-after-free.\n\n BUG: KASAN: slab-use-after-free in _copy_to_user+0x37/0x60\n Read of size 16 at addr ffff888013505260 by task exploit/149\n _copy_to_user+0x37/0x60\n do_tcp_getsockopt+0x158a/0x2460 (net/ipv4/tcp.c:4585)\n tcp_getsockopt+0x91/0xf0\n __sys_getsockopt+0xf7/0x170\n\nFix this by holding rcu_read_lock() around the ca_ops->name access,\nusing READ_ONCE() to load icsk_ca_ops, and copying the name to a\nstack buffer before releasing the lock. Also annotate the relevant\nicsk_ca_ops stores with WRITE_ONCE() to fix the accompanying KCSAN\ndata-race issue."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv4/tcp.c", "net/ipv4/tcp_cong.c", "net/ipv4/tcp_dctcp.c", "net/ipv4/tcp_minisocks.c", "net/ipv4/tcp_output.c"], "versions": [{"version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "lessThan": "a60e62705c17534d6b6539de7b3a40c259e6827f", "status": "affected", "versionType": "git"}, {"version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "lessThan": "4b0930d66dde0a1d1898f0edbbb5496c4dfa5f03", "status": "affected", "versionType": "git"}, {"version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "lessThan": "08dc5c62c09653d1c4ba67a009beb138486c2604", "status": "affected", "versionType": "git"}, {"version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "lessThan": "c1804ef016392dd91267d2207ee43b1de34302ca", "status": "affected", "versionType": "git"}, {"version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "lessThan": "a8e45471afa230c1431c26c8e99ec24377e3b514", "status": "affected", "versionType": "git"}, {"version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "lessThan": "5271b79b7ad68dcb222e893773f92bdabf7750f3", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/ipv4/tcp.c", "net/ipv4/tcp_cong.c", "net/ipv4/tcp_dctcp.c", "net/ipv4/tcp_minisocks.c", "net/ipv4/tcp_output.c"], "versions": [{"version": "5.6", "status": "affected"}, {"version": "0", "lessThan": "5.6", "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": "5.6", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.6.161"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.12.115"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "6.18.59"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "7.2.13"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.6", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a60e62705c17534d6b6539de7b3a40c259e6827f"}, {"url": "https://git.kernel.org/stable/c/4b0930d66dde0a1d1898f0edbbb5496c4dfa5f03"}, {"url": "https://git.kernel.org/stable/c/08dc5c62c09653d1c4ba67a009beb138486c2604"}, {"url": "https://git.kernel.org/stable/c/c1804ef016392dd91267d2207ee43b1de34302ca"}, {"url": "https://git.kernel.org/stable/c/a8e45471afa230c1431c26c8e99ec24377e3b514"}, {"url": "https://git.kernel.org/stable/c/5271b79b7ad68dcb222e893773f92bdabf7750f3"}], "title": "tcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION)", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/ipv4/tcp.c", "net/ipv4/tcp_cong.c", "net/ipv4/tcp_dctcp.c", "net/ipv4/tcp_minisocks.c", "net/ipv4/tcp_output.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a60e62705c17534d6b6539de7b3a40c259e6827f", "status": "affected", "version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "versionType": "git"}, {"lessThan": "4b0930d66dde0a1d1898f0edbbb5496c4dfa5f03", "status": "affected", "version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "versionType": "git"}, {"lessThan": "08dc5c62c09653d1c4ba67a009beb138486c2604", "status": "affected", "version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "versionType": "git"}, {"lessThan": "c1804ef016392dd91267d2207ee43b1de34302ca", "status": "affected", "version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "versionType": "git"}, {"lessThan": "a8e45471afa230c1431c26c8e99ec24377e3b514", "status": "affected", "version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "versionType": "git"}, {"lessThan": "5271b79b7ad68dcb222e893773f92bdabf7750f3", "status": "affected", "version": "0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/ipv4/tcp.c", "net/ipv4/tcp_cong.c", "net/ipv4/tcp_dctcp.c", "net/ipv4/tcp_minisocks.c", "net/ipv4/tcp_output.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.6"}, {"lessThan": "5.6", "status": "unaffected", "version": "0", "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\ntcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION)\n\ndo_tcp_getsockopt() reads icsk->icsk_ca_ops->name without holding\nrcu_read_lock(). Since commit 0baf26b0fcd7 (\"bpf: tcp: Support\ntcp_congestion_ops in bpf\"), icsk_ca_ops can point to dynamically\nallocated BPF struct_ops memory that may be freed concurrently via\nsetsockopt(TCP_CONGESTION), leading to a use-after-free.\n\n BUG: KASAN: slab-use-after-free in _copy_to_user+0x37/0x60\n Read of size 16 at addr ffff888013505260 by task exploit/149\n _copy_to_user+0x37/0x60\n do_tcp_getsockopt+0x158a/0x2460 (net/ipv4/tcp.c:4585)\n tcp_getsockopt+0x91/0xf0\n __sys_getsockopt+0xf7/0x170\n\nFix this by holding rcu_read_lock() around the ca_ops->name access,\nusing READ_ONCE() to load icsk_ca_ops, and copying the name to a\nstack buffer before releasing the lock. Also annotate the relevant\nicsk_ca_ops stores with WRITE_ONCE() to fix the accompanying KCSAN\ndata-race issue."}], "id": "CVE-2026-99139", "lastModified": "2026-10-30T13:21:48.150", "metrics": {}, "published": "2026-10-28T11:17:33.850", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/08dc5c62c09653d1c4ba67a009beb138486c2604"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4b0930d66dde0a1d1898f0edbbb5496c4dfa5f03"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5271b79b7ad68dcb222e893773f92bdabf7750f3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a60e62705c17534d6b6539de7b3a40c259e6827f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a8e45471afa230c1431c26c8e99ec24377e3b514"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c1804ef016392dd91267d2207ee43b1de34302ca"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: kernel: privilege escalation via use-after-free in do_tcp_getsockopt", "id": "2562669", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2562669"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["In the Linux kernel, the following vulnerability has been resolved:\ntcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION)\ndo_tcp_getsockopt() reads icsk->icsk_ca_ops->name without holding\nrcu_read_lock(). Since commit 0baf26b0fcd7 (\"bpf: tcp: Support\ntcp_congestion_ops in bpf\"), icsk_ca_ops can point to dynamically\nallocated BPF struct_ops memory that may be freed concurrently via\nsetsockopt(TCP_CONGESTION), leading to a use-after-free.\nBUG: KASAN: slab-use-after-free in _copy_to_user+0x37/0x60\nRead of size 16 at addr ffff888013505260 by task exploit/149\n_copy_to_user+0x37/0x60\ndo_tcp_getsockopt+0x158a/0x2460 (net/ipv4/tcp.c:4585)\ntcp_getsockopt+0x91/0xf0\n__sys_getsockopt+0xf7/0x170\nFix this by holding rcu_read_lock() around the ca_ops->name access,\nusing READ_ONCE() to load icsk_ca_ops, and copying the name to a\nstack buffer before releasing the lock. Also annotate the relevant\nicsk_ca_ops stores with WRITE_ONCE() to fix the accompanying KCSAN\ndata-race issue.", "A flaw was found in the Linux kernel's Transmission Control Protocol (TCP) subsystem. A race condition occurs when querying TCP congestion control settings without proper locking, which can allow dynamically allocated memory to be released while still being read. A local attacker can exploit this use-after-free flaw through concurrent socket requests to potentially achieve privilege escalation or trigger a system crash, resulting in a Denial of Service (DoS)."], "name": "CVE-2026-99139", "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": "Out of support scope", "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": "Fix deferred", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Fix deferred", "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": "Fix deferred", "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": "2026-10-28T10:34:50Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-99139\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-99139\nhttps://git.kernel.org/stable/c/5271b79b7ad68dcb222e893773f92bdabf7750f3\nhttps://git.kernel.org/stable/c/a8e45471afa230c1431c26c8e99ec24377e3b514\nhttps://git.kernel.org/stable/c/c1804ef016392dd91267d2207ee43b1de34302ca"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2,c1804ef016392dd91267d2207ee43b1de34302ca)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2,a8e45471afa230c1431c26c8e99ec24377e3b514)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2,5271b79b7ad68dcb222e893773f92bdabf7750f3)"}}], "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": "generic", "value": "5.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.6)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.59,6.19.0]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.13,7.3.0]"}}, {"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": "[0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2,c1804ef016392dd91267d2207ee43b1de34302ca)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2,a8e45471afa230c1431c26c8e99ec24377e3b514)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2,5271b79b7ad68dcb222e893773f92bdabf7750f3)"}}], "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": "generic", "value": "5.6"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,5.6)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.59,6.19.0]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.13,7.3.0]"}}, {"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": "2026-10-28T11:45:09.958298+00:00", "updated": "2026-10-30T05:30:09.656216+00:00", "vendors": ["linux", "linux$PRODUCT$linux", "linux$PRODUCT$linux_kernel"]}