{"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"}}}}