{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31570","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-03-09T15:48:24.117Z","datePublished":"2026-04-24T14:35:49.435Z","dateUpdated":"2026-05-11T22:11:20.659Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T22:11:20.659Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: gw: fix OOB heap access in cgw_csum_crc8_rel()\n\ncgw_csum_crc8_rel() correctly computes bounds-safe indices via calc_idx():\n\n    int from = calc_idx(crc8->from_idx, cf->len);\n    int to   = calc_idx(crc8->to_idx,   cf->len);\n    int res  = calc_idx(crc8->result_idx, cf->len);\n\n    if (from < 0 || to < 0 || res < 0)\n        return;\n\nHowever, the loop and the result write then use the raw s8 fields directly\ninstead of the computed variables:\n\n    for (i = crc8->from_idx; ...)        /* BUG: raw negative index */\n    cf->data[crc8->result_idx] = ...;    /* BUG: raw negative index */\n\nWith from_idx = to_idx = result_idx = -64 on a 64-byte CAN FD frame,\ncalc_idx(-64, 64) = 0 so the guard passes, but the loop iterates with\ni = -64, reading cf->data[-64], and the write goes to cf->data[-64].\nThis write might end up to 56 (7.0-rc) or 40 (<= 6.19) bytes before the\nstart of the canfd_frame on the heap.\n\nThe companion function cgw_csum_xor_rel() uses `from`/`to`/`res`\ncorrectly throughout; fix cgw_csum_crc8_rel() to match.\n\nConfirmed with KASAN on linux-7.0-rc2:\n  BUG: KASAN: slab-out-of-bounds in cgw_csum_crc8_rel+0x515/0x5b0\n  Read of size 1 at addr ffff8880076619c8 by task poc_cgw_oob/62\n\nTo configure the can-gw crc8 checksums CAP_NET_ADMIN is needed."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"}}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/gw.c"],"versions":[{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"e7c99348b0612b2bc02d5ce6ff9873261cc7605f","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"999ca48d55a8a46da21519db7e834e5867200379","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"a025283d7f7404c739225e457fb99db2368bb544","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"54ecdf76a55e75c1f5085e440f8ab671a3283ef5","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"c4e8eaa75fa0b6bcbfa5356d6195c4ad0e05e57a","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"84f8b76d24273175a22713e83e90874e1880d801","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"66b689efd08227da2c5ca49b58b30a95d23c695a","status":"affected","versionType":"git"},{"version":"456a8a646b2563438c16a9b27decf9aa717f1ebb","lessThan":"b9c310d72783cc2f30d103eed83920a5a29c671a","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/can/gw.c"],"versions":[{"version":"5.4","status":"affected"},{"version":"0","lessThan":"5.4","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":"6.1.168","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.131","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.80","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.21","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.11","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":"5.4","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.1.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.6.131"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.12.80"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.18.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.19.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/e7c99348b0612b2bc02d5ce6ff9873261cc7605f"},{"url":"https://git.kernel.org/stable/c/999ca48d55a8a46da21519db7e834e5867200379"},{"url":"https://git.kernel.org/stable/c/a025283d7f7404c739225e457fb99db2368bb544"},{"url":"https://git.kernel.org/stable/c/54ecdf76a55e75c1f5085e440f8ab671a3283ef5"},{"url":"https://git.kernel.org/stable/c/c4e8eaa75fa0b6bcbfa5356d6195c4ad0e05e57a"},{"url":"https://git.kernel.org/stable/c/84f8b76d24273175a22713e83e90874e1880d801"},{"url":"https://git.kernel.org/stable/c/66b689efd08227da2c5ca49b58b30a95d23c695a"},{"url":"https://git.kernel.org/stable/c/b9c310d72783cc2f30d103eed83920a5a29c671a"}],"title":"can: gw: fix OOB heap access in cgw_csum_crc8_rel()","x_generator":{"engine":"bippy-1.2.0"}}}}