{"id":"CVE-2026-63964","state":"PUBLISHED","title":"usb: typec: ucsi: ccg: reject firmware images without a ':' record header","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: typec: ucsi: ccg: reject firmware images without a ':' record header\n\ndo_flash() locates the first .cyacd record with\n\n\tp = strnchr(fw->data, fw->size, ':');\n\twhile (p < eof) {\n\t\ts = strnchr(p + 1, eof - p - 1, ':');\n\t\t...\n\t}\n\nIf the firmware image contains no ':' byte,  strnchr() returns NULL.\nNULL compares less than the valid kernel pointer eof, so the loop body\nruns and strnchr() is called with p + 1 == (void *)1 and a length of\nroughly (unsigned long)eof, causing a wonderful crash.\n\nThe not_signed_fw fallthrough earlier in do_flash() and the chip-state\nbranches in ccg_fw_update_needed() allow an unsigned blob to reach this\nloop, so a root user who can place a crafted file under /lib/firmware\nand write the do_flash sysfs attribute can trigger the oops.\n\nBail out with -EINVAL when the initial strnchr() returns NULL.","publishedAt":"2026-07-19T14:55:53.115Z","updatedAt":"2026-07-20T06:41:45.132Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"b41dfc033fe594e152648050e95b9489cd53e9e3","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"2f395ca1263bd181995eb829f5943a83a20db213","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"6526f8684f72391138353642af908803ba70795e","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"3f432b8203066c26770fe6ea591361f10021dd6b","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"a38ed87818b2419090fb1a6338ddce6842b65dfa","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"c8460de584fe5415d212cfdd127d4db90835a450","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"d7486952bf74e546ee3748fb14b2d07881fa6273","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/typec/ucsi/ucsi_ccg.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.2","versionType":"semver"},{"version":"5.10.259","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.210","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.176","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.143","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.93","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.35","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/typec/ucsi/ucsi_ccg.c"]}],"references":["https://git.kernel.org/stable/c/b41dfc033fe594e152648050e95b9489cd53e9e3","https://git.kernel.org/stable/c/2f395ca1263bd181995eb829f5943a83a20db213","https://git.kernel.org/stable/c/6526f8684f72391138353642af908803ba70795e","https://git.kernel.org/stable/c/3f432b8203066c26770fe6ea591361f10021dd6b","https://git.kernel.org/stable/c/c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb","https://git.kernel.org/stable/c/a38ed87818b2419090fb1a6338ddce6842b65dfa","https://git.kernel.org/stable/c/c8460de584fe5415d212cfdd127d4db90835a450","https://git.kernel.org/stable/c/d7486952bf74e546ee3748fb14b2d07881fa6273"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/63xxx/CVE-2026-63964.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63964","state":"PUBLISHED","datePublished":"2026-07-19T14:55:53.115Z","dateUpdated":"2026-07-20T06:41:45.132Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T07:54:57.024Z"},"containers":{"cna":{"title":"usb: typec: ucsi: ccg: reject firmware images without a ':' record header","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: typec: ucsi: ccg: reject firmware images without a ':' record header\n\ndo_flash() locates the first .cyacd record with\n\n\tp = strnchr(fw->data, fw->size, ':');\n\twhile (p < eof) {\n\t\ts = strnchr(p + 1, eof - p - 1, ':');\n\t\t...\n\t}\n\nIf the firmware image contains no ':' byte,  strnchr() returns NULL.\nNULL compares less than the valid kernel pointer eof, so the loop body\nruns and strnchr() is called with p + 1 == (void *)1 and a length of\nroughly (unsigned long)eof, causing a wonderful crash.\n\nThe not_signed_fw fallthrough earlier in do_flash() and the chip-state\nbranches in ccg_fw_update_needed() allow an unsigned blob to reach this\nloop, so a root user who can place a crafted file under /lib/firmware\nand write the do_flash sysfs attribute can trigger the oops.\n\nBail out with -EINVAL when the initial strnchr() returns NULL."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"b41dfc033fe594e152648050e95b9489cd53e9e3","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"2f395ca1263bd181995eb829f5943a83a20db213","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"6526f8684f72391138353642af908803ba70795e","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"3f432b8203066c26770fe6ea591361f10021dd6b","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"a38ed87818b2419090fb1a6338ddce6842b65dfa","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"c8460de584fe5415d212cfdd127d4db90835a450","versionType":"git"},{"version":"5c9ae5a87573d38cfc4c740aafda2fa6ce06e401","status":"affected","lessThan":"d7486952bf74e546ee3748fb14b2d07881fa6273","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/typec/ucsi/ucsi_ccg.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.2","versionType":"semver"},{"version":"5.10.259","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.210","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.176","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.143","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.93","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.35","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/typec/ucsi/ucsi_ccg.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/b41dfc033fe594e152648050e95b9489cd53e9e3"},{"url":"https://git.kernel.org/stable/c/2f395ca1263bd181995eb829f5943a83a20db213"},{"url":"https://git.kernel.org/stable/c/6526f8684f72391138353642af908803ba70795e"},{"url":"https://git.kernel.org/stable/c/3f432b8203066c26770fe6ea591361f10021dd6b"},{"url":"https://git.kernel.org/stable/c/c4ee519b06389e59ba2d6aa722fcc4a02a8bbcbb"},{"url":"https://git.kernel.org/stable/c/a38ed87818b2419090fb1a6338ddce6842b65dfa"},{"url":"https://git.kernel.org/stable/c/c8460de584fe5415d212cfdd127d4db90835a450"},{"url":"https://git.kernel.org/stable/c/d7486952bf74e546ee3748fb14b2d07881fa6273"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-07-20T06:41:45.132Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"5.10.259"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"5.15.210"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"6.1.176"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"6.6.143"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"6.12.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"6.18.35"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"7.0.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.2","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}