{"id":"CVE-2026-74391","state":"PUBLISHED","title":"tracing: Bound synthetic-field strings with seq_buf","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Bound synthetic-field strings with seq_buf\n\nThe synthetic field helpers build a prefixed synthetic variable name and\na generated hist command in fixed MAX_FILTER_STR_VAL buffers. The\ncurrent code appends those strings with raw strcat(), so long key lists,\nfield names, or saved filters can run past the end of the staging\nbuffers.\n\nBuild both strings with seq_buf and propagate -E2BIG if either the\nsynthetic variable name or the generated command exceeds\nMAX_FILTER_STR_VAL. This keeps the existing tracing-side limit while\nusing the helper intended for bounded command construction.\n\n[ sdr: Moved struct seq_buf *s for upside-down x-mas tree formatting ]","publishedAt":"2026-08-15T05:59:05.127Z","updatedAt":"2026-10-30T12:29:55.331Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"9f8ef2e1e95a42044e614b0a5277e3f53f545135","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"0c584c27f6649a93ec12061cc779a4bd8f7c1434","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"88b901fdc1662b131ff908cbd017333b61e7acc8","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"baa333b2700a7fa3529d504529c8c10060fd687c","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"cf334620036ad2250e008c7e7bb6646a3938b7b0","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"f07883450eb14d1cf020b55d9f3a7ec5683bcd26","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.17","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.17","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]}],"references":["https://git.kernel.org/stable/c/9f8ef2e1e95a42044e614b0a5277e3f53f545135","https://git.kernel.org/stable/c/0c584c27f6649a93ec12061cc779a4bd8f7c1434","https://git.kernel.org/stable/c/88b901fdc1662b131ff908cbd017333b61e7acc8","https://git.kernel.org/stable/c/baa333b2700a7fa3529d504529c8c10060fd687c","https://git.kernel.org/stable/c/cf334620036ad2250e008c7e7bb6646a3938b7b0","https://git.kernel.org/stable/c/f07883450eb14d1cf020b55d9f3a7ec5683bcd26"],"weaknesses":[],"ingestedAt":"2026-10-30T12:48:04.825Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74391.json","commit":"1f312381e38164a43607eebab851b151dd16861e","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74391","state":"PUBLISHED","datePublished":"2026-08-15T05:59:05.127Z","dateUpdated":"2026-10-30T12:29:55.331Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.891Z"},"containers":{"cna":{"title":"tracing: Bound synthetic-field strings with seq_buf","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Bound synthetic-field strings with seq_buf\n\nThe synthetic field helpers build a prefixed synthetic variable name and\na generated hist command in fixed MAX_FILTER_STR_VAL buffers. The\ncurrent code appends those strings with raw strcat(), so long key lists,\nfield names, or saved filters can run past the end of the staging\nbuffers.\n\nBuild both strings with seq_buf and propagate -E2BIG if either the\nsynthetic variable name or the generated command exceeds\nMAX_FILTER_STR_VAL. This keeps the existing tracing-side limit while\nusing the helper intended for bounded command construction.\n\n[ sdr: Moved struct seq_buf *s for upside-down x-mas tree formatting ]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"9f8ef2e1e95a42044e614b0a5277e3f53f545135","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"0c584c27f6649a93ec12061cc779a4bd8f7c1434","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"88b901fdc1662b131ff908cbd017333b61e7acc8","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"baa333b2700a7fa3529d504529c8c10060fd687c","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"cf334620036ad2250e008c7e7bb6646a3938b7b0","versionType":"git"},{"version":"02205a6752f223779a1b0e9e8ffacbea6e717851","status":"affected","lessThan":"f07883450eb14d1cf020b55d9f3a7ec5683bcd26","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.17","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.17","versionType":"semver"},{"version":"6.1.191","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/trace_events_hist.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/9f8ef2e1e95a42044e614b0a5277e3f53f545135"},{"url":"https://git.kernel.org/stable/c/0c584c27f6649a93ec12061cc779a4bd8f7c1434"},{"url":"https://git.kernel.org/stable/c/88b901fdc1662b131ff908cbd017333b61e7acc8"},{"url":"https://git.kernel.org/stable/c/baa333b2700a7fa3529d504529c8c10060fd687c"},{"url":"https://git.kernel.org/stable/c/cf334620036ad2250e008c7e7bb6646a3938b7b0"},{"url":"https://git.kernel.org/stable/c/f07883450eb14d1cf020b55d9f3a7ec5683bcd26"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-30T12:29:55.331Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.1.191"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.17","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}