{"id":"CVE-2021-47611","state":"PUBLISHED","title":"mac80211: validate extended element ID is present","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmac80211: validate extended element ID is present\n\nBefore attempting to parse an extended element, verify that\nthe extended element ID is present.","publishedAt":"2024-06-19T14:58:00.362Z","updatedAt":"2026-08-05T08:48:36.304Z","severity":{"score":8.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"03029bb044ccee60adbc93e70713f3ae58abc3a1","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"a19cf6844b509d44ecbd536f33d314d91ecdd2b5","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"7fd214fc7f2ee3a89f91e717e3cfad55f5a27045","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"c62b16f98688ae7bc0ab23a6490481f4ce9b3a49","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"768c0b19b50665e337c96858aa2b7928d6dcf756","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/util.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.19","versionType":"semver"},{"version":"4.19.222","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.168","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.88","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.11","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.16","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/util.c"]}],"references":["https://git.kernel.org/stable/c/03029bb044ccee60adbc93e70713f3ae58abc3a1","https://git.kernel.org/stable/c/a19cf6844b509d44ecbd536f33d314d91ecdd2b5","https://git.kernel.org/stable/c/7fd214fc7f2ee3a89f91e717e3cfad55f5a27045","https://git.kernel.org/stable/c/c62b16f98688ae7bc0ab23a6490481f4ce9b3a49","https://git.kernel.org/stable/c/768c0b19b50665e337c96858aa2b7928d6dcf756"],"weaknesses":[],"ingestedAt":"2026-10-29T19:49:19.404Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2021/47xxx/CVE-2021-47611.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2021-47611","state":"PUBLISHED","datePublished":"2024-06-19T14:58:00.362Z","dateUpdated":"2026-08-05T08:48:36.304Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-06-19T14:55:32.795Z"},"containers":{"cna":{"title":"mac80211: validate extended element ID is present","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmac80211: validate extended element ID is present\n\nBefore attempting to parse an extended element, verify that\nthe extended element ID is present."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"03029bb044ccee60adbc93e70713f3ae58abc3a1","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"a19cf6844b509d44ecbd536f33d314d91ecdd2b5","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"7fd214fc7f2ee3a89f91e717e3cfad55f5a27045","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"c62b16f98688ae7bc0ab23a6490481f4ce9b3a49","versionType":"git"},{"version":"41cbb0f5a29592874355e4159489eb08337cd50e","status":"affected","lessThan":"768c0b19b50665e337c96858aa2b7928d6dcf756","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/util.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.19","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.19","versionType":"semver"},{"version":"4.19.222","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.168","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.88","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.11","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.16","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/util.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/03029bb044ccee60adbc93e70713f3ae58abc3a1"},{"url":"https://git.kernel.org/stable/c/a19cf6844b509d44ecbd536f33d314d91ecdd2b5"},{"url":"https://git.kernel.org/stable/c/7fd214fc7f2ee3a89f91e717e3cfad55f5a27045"},{"url":"https://git.kernel.org/stable/c/c62b16f98688ae7bc0ab23a6490481f4ce9b3a49"},{"url":"https://git.kernel.org/stable/c/768c0b19b50665e337c96858aa2b7928d6dcf756"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","baseScore":8.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:A - The bug is in mac80211 IE parsing of received 802.11 management frames (beacons/probe responses/IBSS/mesh), which an attacker on the same Wi‑Fi RF segment can inject; this is Adjacent, not routable Network.\nAC:L - An attacker can reliably send a WLAN_EID_EXTENSION element with datalen=0 (optionally followed by ext ID 35) so elem->data[0] and the underflown len=255 path are hit with no race or layout dependency.\nPR:N - Beacon and probe-response IE parsing runs on unauthenticated over-the-air frames before any host credentials or capabilities are involved, so no privileges on the victim are required.\nUI:N - mac80211 parses these IEs automatically on the RX/workqueue path whenever Wi‑Fi is operating or scanning; no extra user action is required.\nS:U - Impact is confined to the host kernel wireless stack and does not cross a VM, IOMMU, or other separate security authority.\nC:H - With datalen=0, len underflows to 255 and extension parsing (especially WLAN_EID_EXT_HE_CAPABILITY, which applies no length check) can read far past the IE buffer into adjacent kernel memory, which is an unbounded OOB read rather than a few-byte leak.\nI:N - The defect is an out-of-bounds read that may copy OOB bytes into fixed-size HE capability fields; destination PPE buffers are sized for the maximum computed length, so there is no OOB write or UAF write primitive.\nA:H - Reading tens to hundreds of bytes past the IE/skb buffer can fault on unmapped memory and oops/panic the kernel, yielding a complete denial of service."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T08:48:36.304Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"4.19.222"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.4.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.10.88"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.15.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19","versionEndExcluding":"5.16"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2024-06-20T13:48:17.643512Z","id":"CVE-2021-47611","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-06-20T13:48:23.836Z"}},{"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/03029bb044ccee60adbc93e70713f3ae58abc3a1","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/a19cf6844b509d44ecbd536f33d314d91ecdd2b5","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/7fd214fc7f2ee3a89f91e717e3cfad55f5a27045","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/c62b16f98688ae7bc0ab23a6490481f4ce9b3a49","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/768c0b19b50665e337c96858aa2b7928d6dcf756","tags":["x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-04T05:47:40.575Z"}}]}}}