{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-23397", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:46.011Z", "datePublished": "2026-03-26T10:22:49.954Z", "dateUpdated": "2026-07-14T12:46:54.769Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T22:06:07.152Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnfnetlink_osf: validate individual option lengths in fingerprints\n\nnfnl_osf_add_callback() validates opt_num bounds and string\nNUL-termination but does not check individual option length fields.\nA zero-length option causes nf_osf_match_one() to enter the option\nmatching loop even when foptsize sums to zero, which matches packets\nwith no TCP options where ctx->optp is NULL:\n\n Oops: general protection fault\n KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98)\n Call Trace:\n nf_osf_match (net/netfilter/nfnetlink_osf.c:227)\n xt_osf_match_packet (net/netfilter/xt_osf.c:32)\n ipt_do_table (net/ipv4/netfilter/ip_tables.c:293)\n nf_hook_slow (net/netfilter/core.c:623)\n ip_local_deliver (net/ipv4/ip_input.c:262)\n ip_rcv (net/ipv4/ip_input.c:573)\n\nAdditionally, an MSS option (kind=2) with length < 4 causes\nout-of-bounds reads when nf_osf_match_one() unconditionally accesses\noptp[2] and optp[3] for MSS value extraction. While RFC 9293\nsection 3.2 specifies that the MSS option is always exactly 4\nbytes (Kind=2, Length=4), the check uses \"< 4\" rather than\n\"!= 4\" because lengths greater than 4 do not cause memory\nsafety issues -- the buffer is guaranteed to be at least\nfoptsize bytes by the ctx->optsize == foptsize check.\n\nReject fingerprints where any option has zero length, or where an MSS\noption has length less than 4, at add time rather than trusting these\nvalues in the packet matching hot path." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nfnetlink_osf.c" ], "versions": [ { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "e9cf17b91e733fec725ebcc0b3098bc5ccd505e0", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "3c11b5c2436a3a5b450612ab160e3a525b28cfb5", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "aa0574182c46963c3cdb8cde46ec93aca21100d8", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "224f4678812e1a7bc8341bcb666773a0aec5ea6f", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "ec8bf0571b142f29dc0b68ae2ac3952f7a464b38", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "3932620c04c2938c93c0890c225960d3d34ba355", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "4c6aa008b913e808c4f4d3cde36cb1d9bb5967c6", "status": "affected", "versionType": "git" }, { "version": "11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384", "lessThan": "dbdfaae9609629a9569362e3b8f33d0a20fd783c", "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/netfilter/nfnetlink_osf.c" ], "versions": [ { "version": "2.6.31", "status": "affected" }, { "version": "0", "lessThan": "2.6.31", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.253", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.203", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.167", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.130", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.78", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.20", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.10", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "2.6.31", "versionEndExcluding": "5.10.253" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "5.15.203" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "6.1.167" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "6.6.130" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "6.12.78" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "6.18.20" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "6.19.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.31", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/e9cf17b91e733fec725ebcc0b3098bc5ccd505e0" }, { "url": "https://git.kernel.org/stable/c/3c11b5c2436a3a5b450612ab160e3a525b28cfb5" }, { "url": "https://git.kernel.org/stable/c/aa0574182c46963c3cdb8cde46ec93aca21100d8" }, { "url": "https://git.kernel.org/stable/c/224f4678812e1a7bc8341bcb666773a0aec5ea6f" }, { "url": "https://git.kernel.org/stable/c/ec8bf0571b142f29dc0b68ae2ac3952f7a464b38" }, { "url": "https://git.kernel.org/stable/c/3932620c04c2938c93c0890c225960d3d34ba355" }, { "url": "https://git.kernel.org/stable/c/4c6aa008b913e808c4f4d3cde36cb1d9bb5967c6" }, { "url": "https://git.kernel.org/stable/c/dbdfaae9609629a9569362e3b8f33d0a20fd783c" } ], "title": "nfnetlink_osf: validate individual option lengths in fingerprints", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "x_adpType": "supplier", "providerMetadata": { "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-07-14T12:46:54.769Z" }, "affected": [ { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": 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"versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" } ], "references": [ { "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html" }, { "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html" } ] } ] } }