{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89897", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.773Z", "datePublished": "2026-09-16T10:31:58.184Z", "dateUpdated": "2026-10-19T08:54:30.169Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:54:30.169Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: cec: Serialize exclusive follower delivery\n\ncec_receive_notify() reads the exclusive follower pointer without the\nadapter lock. Serialize the no-follower check and message delivery\nagainst mode changes and release." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:A - cec_receive_notify() runs from cec_received_msg_ts() on HDMI-CEC frames a peer places on the shared CEC line. HDMI-CEC is a multi-drop bus among TVs, AVRs, streaming sticks, and conference or automotive HDMI sources, matching CAN/Bluetooth adjacent-segment scoring rather than Internet-routable Network.\nAC:H - The use-after-free requires cec_release() to kfree the exclusive-follower cec_fh after the unlocked pointer load in cec_receive_notify(). A CEC peer can flood receive but cannot close that filehandle, so success depends on concurrent local teardown the attacker cannot initiate.\nPR:N - HDMI-CEC has no authentication. Any device on the same CEC bus can emit frames that the adapter delivers into cec_received_msg_ts() with no Linux account, capability, or user-namespace check on the host.\nUI:N - Once the adapter is configured and receiving, which is normal for TVs, Android HDMI-CEC, SBCs, and automotive head units that claim a logical address at boot, RX delivery and any concurrent follower close run without a mount, prompt, or other interactive victim step.\nS:U - The use-after-free is of the kmalloc'd struct cec_fh inside the host kernel CEC core and does not cross a VM, IOMMU, or other separate security-authority boundary.\nC:H - After cec_release() kfree()s the exclusive follower, cec_queue_msg_fh() still locks and walks lists on the dangling cec_fh. That kernel heap use-after-free enables disclosure of reused object contents.\nI:H - cec_queue_msg_fh() writes the freed filehandle via mutex operations, list_add_tail of a new cec_msg_entry, and wake_up_interruptible, a heap use-after-free write and control-flow hijack primitive.\nA:H - Using a freed cec_fh from the receive path causes a kernel oops or panic even when not fully exploited for code execution, taking down the host." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/media/cec/core/cec-adap.c" ], "versions": [ { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "efc829b4b937f98c4467bffe9243f756b7cfbf7f", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "cac577854826950dda4d53569728b1da6c1425d5", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "4b532b271c91790b7ab661cd488a7ad36f5c4f6b", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "271e57a936dcdbaecb4b1bd005d9a285bbe60ab4", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "df941e6851da17fc53c7f6af2bdcc7383d17babc", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "5c62095acc2a952099688774513c4a637bcdb2b5", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "ae614f48712156fb0f55b207338d48d422c58bc0", "status": "affected", "versionType": "git" }, { "version": "9881fe0ca187c213eb3a6a8e78e45ad4d1cec171", "lessThan": "1924d0788caa6c66fd320dd4704fae99487fd2c7", "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/core/cec-adap.c" ], "versions": [ { "version": "4.8", "status": "affected" }, { "version": "0", "lessThan": "4.8", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "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", "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": "4.8", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.12.110" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "6.18.51" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "7.2.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.8", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/efc829b4b937f98c4467bffe9243f756b7cfbf7f" }, { "url": "https://git.kernel.org/stable/c/cac577854826950dda4d53569728b1da6c1425d5" }, { "url": "https://git.kernel.org/stable/c/4b532b271c91790b7ab661cd488a7ad36f5c4f6b" }, { "url": "https://git.kernel.org/stable/c/271e57a936dcdbaecb4b1bd005d9a285bbe60ab4" }, { "url": "https://git.kernel.org/stable/c/df941e6851da17fc53c7f6af2bdcc7383d17babc" }, { "url": "https://git.kernel.org/stable/c/5c62095acc2a952099688774513c4a637bcdb2b5" }, { "url": "https://git.kernel.org/stable/c/ae614f48712156fb0f55b207338d48d422c58bc0" }, { "url": "https://git.kernel.org/stable/c/1924d0788caa6c66fd320dd4704fae99487fd2c7" } ], "title": "media: cec: Serialize exclusive follower delivery", "x_generator": { "engine": "bippy-1.2.0" } } } }