{"id":"CVE-2026-31532","state":"PUBLISHED","title":"can: raw: fix ro->uniq use-after-free in raw_rcv()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: raw: fix ro->uniq use-after-free in raw_rcv()\n\nraw_release() unregisters raw CAN receive filters via can_rx_unregister(),\nbut receiver deletion is deferred with call_rcu(). This leaves a window\nwhere raw_rcv() may still be running in an RCU read-side critical section\nafter raw_release() frees ro->uniq, leading to a use-after-free of the\npercpu uniq storage.\n\nMove free_percpu(ro->uniq) out of raw_release() and into a raw-specific\nsocket destructor. can_rx_unregister() takes an extra reference to the\nsocket and only drops it from the RCU callback, so freeing uniq from\nsk_destruct ensures the percpu area is not released until the relevant\ncallbacks have drained.\n\n[mkl: applied manually]","publishedAt":"2026-04-23T11:12:44.829Z","updatedAt":"2026-10-19T18:45:55.225Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"1de30576a6dfeaaa27ef91fa272e6b9240b6fbd3","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"64c8553decf5a5f2417bd54761ea0a832c56c4ca","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"3f43f12fde34737fba091b7e3ab391e14ddbb0be","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"5e9cfffad898bbeaafd0ea608a6d267362f050fc","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"572f0bf536ebc14f6e7da3d21a85cf076de8358e","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"1a0f2de81f7fbdc538fc72d7d74609b79bc83cc0","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"7201a531b9a5ed892bfda5ded9194ef622de8ffa","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"34c1741254ff972e8375faf176678a248826fe3a","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"a535a9217ca3f2fccedaafb2fddb4c48f27d36dc","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/raw.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.1","versionType":"semver"},{"version":"5.10.258","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.209","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.136","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.83","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.24","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.14","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0.1","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/raw.c"]}],"references":["https://git.kernel.org/stable/c/1de30576a6dfeaaa27ef91fa272e6b9240b6fbd3","https://git.kernel.org/stable/c/64c8553decf5a5f2417bd54761ea0a832c56c4ca","https://git.kernel.org/stable/c/3f43f12fde34737fba091b7e3ab391e14ddbb0be","https://git.kernel.org/stable/c/5e9cfffad898bbeaafd0ea608a6d267362f050fc","https://git.kernel.org/stable/c/572f0bf536ebc14f6e7da3d21a85cf076de8358e","https://git.kernel.org/stable/c/1a0f2de81f7fbdc538fc72d7d74609b79bc83cc0","https://git.kernel.org/stable/c/7201a531b9a5ed892bfda5ded9194ef622de8ffa","https://git.kernel.org/stable/c/34c1741254ff972e8375faf176678a248826fe3a","https://git.kernel.org/stable/c/a535a9217ca3f2fccedaafb2fddb4c48f27d36dc","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-416"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/31xxx/CVE-2026-31532.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31532","state":"PUBLISHED","datePublished":"2026-04-23T11:12:44.829Z","dateUpdated":"2026-10-19T18:45:55.225Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-03-09T15:48:24.112Z"},"containers":{"cna":{"title":"can: raw: fix ro->uniq use-after-free in raw_rcv()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: raw: fix ro->uniq use-after-free in raw_rcv()\n\nraw_release() unregisters raw CAN receive filters via can_rx_unregister(),\nbut receiver deletion is deferred with call_rcu(). This leaves a window\nwhere raw_rcv() may still be running in an RCU read-side critical section\nafter raw_release() frees ro->uniq, leading to a use-after-free of the\npercpu uniq storage.\n\nMove free_percpu(ro->uniq) out of raw_release() and into a raw-specific\nsocket destructor. can_rx_unregister() takes an extra reference to the\nsocket and only drops it from the RCU callback, so freeing uniq from\nsk_destruct ensures the percpu area is not released until the relevant\ncallbacks have drained.\n\n[mkl: applied manually]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"1de30576a6dfeaaa27ef91fa272e6b9240b6fbd3","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"64c8553decf5a5f2417bd54761ea0a832c56c4ca","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"3f43f12fde34737fba091b7e3ab391e14ddbb0be","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"5e9cfffad898bbeaafd0ea608a6d267362f050fc","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"572f0bf536ebc14f6e7da3d21a85cf076de8358e","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"1a0f2de81f7fbdc538fc72d7d74609b79bc83cc0","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"7201a531b9a5ed892bfda5ded9194ef622de8ffa","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"34c1741254ff972e8375faf176678a248826fe3a","versionType":"git"},{"version":"514ac99c64b22d83b52dfee3b8becaa69a92bc4a","status":"affected","lessThan":"a535a9217ca3f2fccedaafb2fddb4c48f27d36dc","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/raw.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.1","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.1","versionType":"semver"},{"version":"5.10.258","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.209","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.136","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.83","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.24","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.14","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0.1","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/can/raw.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/1de30576a6dfeaaa27ef91fa272e6b9240b6fbd3"},{"url":"https://git.kernel.org/stable/c/64c8553decf5a5f2417bd54761ea0a832c56c4ca"},{"url":"https://git.kernel.org/stable/c/3f43f12fde34737fba091b7e3ab391e14ddbb0be"},{"url":"https://git.kernel.org/stable/c/5e9cfffad898bbeaafd0ea608a6d267362f050fc"},{"url":"https://git.kernel.org/stable/c/572f0bf536ebc14f6e7da3d21a85cf076de8358e"},{"url":"https://git.kernel.org/stable/c/1a0f2de81f7fbdc538fc72d7d74609b79bc83cc0"},{"url":"https://git.kernel.org/stable/c/7201a531b9a5ed892bfda5ded9194ef622de8ffa"},{"url":"https://git.kernel.org/stable/c/34c1741254ff972e8375faf176678a248826fe3a"},{"url":"https://git.kernel.org/stable/c/a535a9217ca3f2fccedaafb2fddb4c48f27d36dc"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires local access to create/bind/close CAN_RAW sockets and race them with CAN frame delivery into raw_rcv(). Received CAN frames can trigger the vulnerable callback, but the attacker-controlled setup and free path are local socket operations.\nAC:L - The race is between attacker-controlled socket teardown/filter unregistration and attacker-controlled CAN frame generation, for example using concurrent local sockets and loopback/vcan or an existing CAN interface. No unusual external condition is required beyond timing that can be retried.\nPR:L - CAN_RAW socket creation, bind, setsockopt, send, and close in this path do not impose a CAP_NET_RAW or CAP_NET_ADMIN check for an existing CAN device. If a virtual CAN device must be created, CAP_NET_ADMIN in a user namespace may suffice, so this is still not real init-namespace root.\nUI:N - No victim action is required once the attacker can run local code. The attacker can create the sockets, register filters, generate frames, and close sockets themselves.\nS:U - The vulnerable object and resulting corruption are within the kernel networking/CAN security authority. This is a standard kernel memory corruption issue, not a cross-VM or hardware boundary escape.\nC:H - This is a use-after-free of per-CPU storage accessed from raw_rcv(), and the freed area may be reallocated before the callback reads it. Per the kernel scoring guidance, UAF memory corruption is treated as enabling high confidentiality impact.\nI:H - raw_rcv() writes skb pointers, hashes, and counters through the freed ro->uniq pointer, corrupting whatever per-CPU object reuses that storage. As a UAF with kernel memory corruption, it is defensibly scored as high integrity impact.\nA:H - The stale per-CPU pointer can lead to invalid memory accesses or corruption during softirq CAN receive processing. A kernel oops/panic is a direct plausible outcome."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:23:19.603Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"5.10.258"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"5.15.209"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"6.6.136"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"6.12.83"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"6.18.24"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"6.19.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"7.0.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:16:54.579Z"},"x_adpType":"supplier"},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-31532","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:10:40.984593Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-416","lang":"en","type":"CWE","description":"CWE-416 Use After Free"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T18:45:55.225Z"}}]}}}