{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-43383","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-05-01T14:12:56.006Z","datePublished":"2026-05-08T14:21:30.704Z","dateUpdated":"2026-05-11T06:34:01.101Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T06:34:01.101Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tcp-md5: Fix MAC comparison to be constant-time\n\nTo prevent timing attacks, MACs need to be compared in constant\ntime.  Use the appropriate helper function for this."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H","baseScore":9.4,"baseSeverity":"CRITICAL"}}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/Kconfig","net/ipv4/tcp.c","net/ipv4/tcp_ipv4.c","net/ipv6/tcp_ipv6.c"],"versions":[{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"821c8751fdeecdeecabeb11704dd33439c9e4bbc","status":"affected","versionType":"git"},{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"345a9530756528d7ca407663d659c3c40e75c3dd","status":"affected","versionType":"git"},{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"5d305a95130a8d08b9545e47f1e18d29d59866cb","status":"affected","versionType":"git"},{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"02669e2a4d207068edce7e8b5fafd85822018ce6","status":"affected","versionType":"git"},{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"ae3831b44f477de048287493e184fc3ff913b624","status":"affected","versionType":"git"},{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"b502e97e29d791ff7a8051f29a414535739be218","status":"affected","versionType":"git"},{"version":"cfb6eeb4c860592edd123fdea908d23c6ad1c7dc","lessThan":"46d0d6f50dab706637f4c18a470aac20a21900d3","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/ipv4/Kconfig","net/ipv4/tcp.c","net/ipv4/tcp_ipv4.c","net/ipv6/tcp_ipv6.c"],"versions":[{"version":"2.6.20","status":"affected"},{"version":"0","lessThan":"2.6.20","status":"unaffected","versionType":"semver"},{"version":"5.10.253","lessThanOrEqual":"5.10.*","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":"6.18.19","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.9","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":"2.6.20","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.1.167"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.12.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.18.19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"6.19.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.20","versionEndExcluding":"7.0"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/821c8751fdeecdeecabeb11704dd33439c9e4bbc"},{"url":"https://git.kernel.org/stable/c/345a9530756528d7ca407663d659c3c40e75c3dd"},{"url":"https://git.kernel.org/stable/c/5d305a95130a8d08b9545e47f1e18d29d59866cb"},{"url":"https://git.kernel.org/stable/c/02669e2a4d207068edce7e8b5fafd85822018ce6"},{"url":"https://git.kernel.org/stable/c/ae3831b44f477de048287493e184fc3ff913b624"},{"url":"https://git.kernel.org/stable/c/b502e97e29d791ff7a8051f29a414535739be218"},{"url":"https://git.kernel.org/stable/c/46d0d6f50dab706637f4c18a470aac20a21900d3"}],"title":"net/tcp-md5: Fix MAC comparison to be constant-time","x_generator":{"engine":"bippy-1.2.0"}}}}