{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-98643", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-98643", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-10-18T15:20:14.561Z", "updatedAt": "2026-10-19T09:23:12.946Z", "importedAt": "2026-10-24T01:58:41.756Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "bpf: Fix out-of-bounds read of rtt_min in sock_ops", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix out-of-bounds read of rtt_min in sock_ops\n\nA sockops prog reading skops->rtt_min never checks the sk type: on the\ntcp_conn_request() path sock_ops->sk is a request_sock (non-full), and the\nctx rewrite casts it to a tcp_sock (full) and reads rtt_min past the end of\nthe request_sock, returning dirty adjacent memory.\n\n\tSEC(\"sockops\")\n\tint prog(struct bpf_sock_ops *skops)\n\t{\n\t\tswitch (skops->op) {\n\t\tcase BPF_SOCK_OPS_RWND_INIT:\n\t\t\tleak = skops->rtt_min; /* reads the request_sock OOB */\n\t\t...\n\t\t}\n\t}\n\nFor instance one such read returned rtt_min=0xffff8881, the high half of a\nleaked kernel pointer.\n\nGuarding that cast is exactly what SOCK_OPS_GET_FIELD() does -- it checks\nis_locked_tcp_sock and returns 0 when sock_ops->sk is not a locked full\nsocket. Every other tcp_sock field in sock_ops goes through it; rtt_min is\nthe only one open-coded, so it skips the check.\n\nRead rtt_min through SOCK_OPS_GET_FIELD() too. rtt_min is a bit special:\nit is a struct minmax and we only want the current min, so pass\nrtt_min.s[0].v. That is equivalent to the old hand-computed offset\n\n\toffsetof(struct tcp_sock, rtt_min) + sizeof_field(struct minmax_sample, t)\n\n(s[0] sits at rtt_min + 0 and .v at + sizeof(.t), i.e. what minmax_get()\nreturns), so the loaded field is unchanged and only the full-sock guard is\nadded. The two BUILD_BUG_ON()s that protected the hand-computed offset\nare no longer needed.\n\nBefore patch:\n\n\t0: r1 = *(u64 *)(r1 +0) ; r1 = skops->sk\n\t1: r1 = *(u32 *)(r1 +2324) ; ((tcp_sock *)sk)->rtt_min.s[0].v\n\nAfter patch:\n\n\t0: *(u64 *)(r1 +56) = r9\n\t1: r9 = *(u8 *)(r1 +50) ; is_locked_tcp_sock\n\t2: if r9 == 0 goto pc+4 ; not a locked full sock -> 0\n\t3: r9 = *(u64 *)(r1 +56)\n\t4: r1 = *(u64 *)(r1 +0) ; r1 = skops->sk\n\t5: r1 = *(u32 *)(r1 +2324) ; rtt_min.s[0].v\n\t6: goto pc+2\n\t7: r9 = *(u64 *)(r1 +56)\n\t8: r1 = 0", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "0c796efa919f52f788c22c79d1f1b70321696b3d" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "fc9d0e6e9d86fbefe7b8fe6ee49f4cf102add79d" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "fd6bf2721933d8c90bc4ce57f3e204c9295e7e3f" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "a8a9becbac93a9f54f4d565f1f3005eb08a7912f" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "3a46f14e6cf375f3ca38f8f6e6524749e24ea0a8" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "6785313d4fac96afb21ef193610c1fa88b1a9e64" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "cba54d142c43ec96d8c4d566f66439e8c0afded7" }, { "version": "44f0e43037d3a17b043843ba67610ac7c7e37db6", "status": "affected", "versionType": "git", "lessThan": "75f8cf22463d82bb1fb0239a3d485fc8f4c8ef03" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.16", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.16" }, { "version": "5.10.271", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.222", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.189", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.158", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.112", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.55", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "7.2.9", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "7.2.*" }, { "version": "7.3", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }