{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89898","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.773Z","datePublished":"2026-09-16T10:31:58.901Z","dateUpdated":"2026-09-16T14:39:47.656Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-16T14:39:47.656Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: cec: extron-da-hd-4k-plus: add sanity check\n\nAdd check to prevent overflowing msg.msg[] in case the incoming data\nis malformed."}],"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"},"scenarios":[{"lang":"en","value":"AV:A - extron_process_received() hex-decodes Ceci/Ceco lines the Extron DA HD 4K Plus reports from its HDMI ports over USB-serial; a malicious HDMI-CEC source on the same splitter bus (conference-room laptop, signage player) can supply those frames, with a USB gadget impersonating the Extron only an extra physical path.\nAC:L - A crafted Ceci/Ceco line of more than 16 %XX triplets deterministically writes past msg.msg[16]; the attacker fully controls the HDMI-CEC or USB-serial payload, and no race or attacker-uncontrollable memory layout is required.\nPR:N - HDMI-CEC and the Extron USB-serial reports are parsed in extron_interrupt() with no host authentication; an adjacent HDMI device or malicious USB ACM gadget needs no account or capability on the Linux host.\nUI:N - Once the Extron is bound via serport, incoming serial lines are parsed automatically in the interrupt handler; an already-connected HDMI source can trigger the overflow without a victim opening a file or clicking.\nS:U - The overflow corrupts only the host kernel that runs this CEC USB driver and does not cross a VM, IOMMU, or other separate security authority.\nC:H - Attacker-chosen hex bytes are written past the 16-byte on-stack msg.msg[] array (a 256-byte line yields up to ~82 decoded bytes), corrupting kernel stack contents and enabling disclosure of adjacent kernel memory.\nI:H - The same out-of-bounds stores smash the kernel stack frame, including saved control data and the return address, enabling control-flow hijacking and arbitrary kernel writes.\nA:H - Overflowing the on-stack cec_msg produces a kernel oops or panic from stack-canary abort or corrupted control data, so the host can be crashed at will."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c"],"versions":[{"version":"056f2821b631df2b94d3b017fd1e1eef918ed98d","lessThan":"00c13b4ab481a09d915d099815cff1b10926ddd9","status":"affected","versionType":"git"},{"version":"056f2821b631df2b94d3b017fd1e1eef918ed98d","lessThan":"673611cc2ab9769929644ce879f7ea34932a3011","status":"affected","versionType":"git"},{"version":"056f2821b631df2b94d3b017fd1e1eef918ed98d","lessThan":"7ad2fec276946a0dedfa54eb26fc38c4fc6a6034","status":"affected","versionType":"git"},{"version":"056f2821b631df2b94d3b017fd1e1eef918ed98d","lessThan":"abac9820b26b5cfcb01eb79efe2abdd0ac7e07c3","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/media/cec/usb/extron-da-hd-4k-plus/extron-da-hd-4k-plus.c"],"versions":[{"version":"6.12","status":"affected"},{"version":"0","lessThan":"6.12","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.51","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.5","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"6.12","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/00c13b4ab481a09d915d099815cff1b10926ddd9"},{"url":"https://git.kernel.org/stable/c/673611cc2ab9769929644ce879f7ea34932a3011"},{"url":"https://git.kernel.org/stable/c/7ad2fec276946a0dedfa54eb26fc38c4fc6a6034"},{"url":"https://git.kernel.org/stable/c/abac9820b26b5cfcb01eb79efe2abdd0ac7e07c3"}],"title":"media: cec: extron-da-hd-4k-plus: add sanity check","x_generator":{"engine":"bippy-1.2.0"}}}}