{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-68320","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-30T09:28:09.382Z","datePublished":"2026-08-10T12:02:55.144Z","dateUpdated":"2026-08-19T16:33:10.661Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-19T16:33:10.661Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: fix auth_chunk_list capacity check in sctp_auth_ep_add_chunkid\n\nsctp_auth_ep_add_chunkid() uses SCTP_NUM_CHUNK_TYPES (20) as the\ncapacity limit for ep->auth_chunk_list, allowing it to hold up to\n20 chunk entries (param_hdr.length up to 24). However, the copy\ndestination asoc->c.auth_chunks in struct sctp_cookie is only\nSCTP_AUTH_MAX_CHUNKS (16) entries (20 bytes). When more than 16\nchunks are added, sctp_association_init() memcpy overflows the\ndestination by up to 4 bytes.\n\nFix by using SCTP_AUTH_MAX_CHUNKS as the capacity limit, matching\nthe destination capacity."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H","baseScore":7.3,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The overflow condition can only be created locally: an attacker must call setsockopt(SCTP_AUTH_SUPPORTED) and then setsockopt(SCTP_AUTH_CHUNK) more than 16 times on an SCTP socket they own. A remote peer can trigger the memcpy by connecting to such a socket, but cannot itself populate the oversized chunk list.\nAC:L - The sequence is fully deterministic and entirely under attacker control — enable AUTH, add 17-20 distinct chunk IDs, then create an association via connect() or accept(); no race, timing window, or memory-layout condition is involved.\nPR:L - Creating an IPPROTO_SCTP socket and issuing SCTP_AUTH_SUPPORTED/SCTP_AUTH_CHUNK setsockopts requires no capability; sctp_setsockopt_auth_supported() enables AUTH per-endpoint regardless of the net.sctp.auth_enable sysctl, so any unprivileged local user reaches the bug.\nUI:N - The attacker performs every step from their own process — socket setup, setsockopt calls, and association establishment — with no action required from any other user or administrator.\nS:U - The corruption and the over-read are confined to the kernel's own SCTP association object; no other security authority or privilege domain is crossed.\nC:L - sctp_make_init()/sctp_make_init_ack() copy ntohs(auth_chunks->length) bytes from the 20-byte field, emitting up to 4 bytes past it (the adjacent raw_addr_list_len) inside the CHUNKS parameter of INIT/INIT-ACK sent to the remote peer — a real but small, strictly bounded out-of-bounds read.\nI:H - sctp_association_init() writes up to 4 bytes of fully attacker-chosen data (the chunk-ID values) past the end of asoc->c.auth_chunks into the adjacent kernel struct field, an out-of-bounds write of controlled content into kernel memory.\nA:H - On CONFIG_FORTIFY_SOURCE kernels the memcpy is flagged as a field-spanning write and emits a WARN, which is fatal on the widely used panic_on_warn configurations, and the out-of-bounds write itself corrupts SCTP association state; the trigger is cheap and repeatable by any local user."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sctp/auth.c"],"versions":[{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"3d22a7da2e264f407c729f33a0a346ff76108bc6","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"6837c1c19a259518974cbc5a52017646e3906564","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"54bb4c03fa17cdcb157c26c33e60a78cf32960f5","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"5a365f1e423444c5da7eb689a8661633dad43e48","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"886e28e14ab655012779016d251fef53d103aa12","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"11092d79eb2b7c0068382f72fc2416d1786bb2e0","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"b6ea3dda09eb4d5caf7bbc00f857688cf9e98255","status":"affected","versionType":"git"},{"version":"1f485649f52929d9937b346a920a522a7363e202","lessThan":"ff04b26794a16a8a879eb4fd2c02c2d6b03850e9","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/sctp/auth.c"],"versions":[{"version":"2.6.24","status":"affected"},{"version":"0","lessThan":"2.6.24","status":"unaffected","versionType":"semver"},{"version":"5.10.265","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.216","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.183","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.148","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.101","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.42","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.6","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","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":"2.6.24","versionEndExcluding":"5.10.265"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"5.15.216"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"6.1.183"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"7.1.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.24","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/3d22a7da2e264f407c729f33a0a346ff76108bc6"},{"url":"https://git.kernel.org/stable/c/6837c1c19a259518974cbc5a52017646e3906564"},{"url":"https://git.kernel.org/stable/c/54bb4c03fa17cdcb157c26c33e60a78cf32960f5"},{"url":"https://git.kernel.org/stable/c/5a365f1e423444c5da7eb689a8661633dad43e48"},{"url":"https://git.kernel.org/stable/c/886e28e14ab655012779016d251fef53d103aa12"},{"url":"https://git.kernel.org/stable/c/11092d79eb2b7c0068382f72fc2416d1786bb2e0"},{"url":"https://git.kernel.org/stable/c/b6ea3dda09eb4d5caf7bbc00f857688cf9e98255"},{"url":"https://git.kernel.org/stable/c/ff04b26794a16a8a879eb4fd2c02c2d6b03850e9"}],"title":"sctp: fix auth_chunk_list capacity check in sctp_auth_ep_add_chunkid","x_generator":{"engine":"bippy-1.2.0"}}}}