{"id":"CVE-2026-80601","state":"PUBLISHED","title":"batman-adv: gw: acquire ethernet header only after skb realloc","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: gw: acquire ethernet header only after skb realloc\n\nThe pskb_may_pull() called by batadv_get_vid() could reallocate the buffer\nbehind the skb. Variables which were pointing to the old buffer need to be\nreassigned to avoid an use-after-free.","publishedAt":"2026-08-28T06:48:27.948Z","updatedAt":"2026-10-16T19:26:29.891Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/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":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"2760b38222c8828b075802342fe3b91eb823d542","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"6c37f1166549c999ccd164b0cb6462d1ae68f8f6","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"b79884a5567bf788fb76c30832467cf6a56f3c0d","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"afac8096bde4948e3caa7e4dd733867cfbd3018e","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"e3f4325e35dd6e76b80665f3510738ce34819753","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"e6b43acd34b219b807e65096ce207b087942779d","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"916dac5f2944f63f07f7b501acbea6737dbbed0e","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"77880a3be88d378d60cc1e8f8ec70430e2ed0518","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/batman-adv/gateway_client.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.14","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/batman-adv/gateway_client.c"]}],"references":["https://git.kernel.org/stable/c/2760b38222c8828b075802342fe3b91eb823d542","https://git.kernel.org/stable/c/6c37f1166549c999ccd164b0cb6462d1ae68f8f6","https://git.kernel.org/stable/c/b79884a5567bf788fb76c30832467cf6a56f3c0d","https://git.kernel.org/stable/c/afac8096bde4948e3caa7e4dd733867cfbd3018e","https://git.kernel.org/stable/c/e3f4325e35dd6e76b80665f3510738ce34819753","https://git.kernel.org/stable/c/e6b43acd34b219b807e65096ce207b087942779d","https://git.kernel.org/stable/c/916dac5f2944f63f07f7b501acbea6737dbbed0e","https://git.kernel.org/stable/c/77880a3be88d378d60cc1e8f8ec70430e2ed0518"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80601.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80601","state":"PUBLISHED","datePublished":"2026-08-28T06:48:27.948Z","dateUpdated":"2026-10-16T19:26:29.891Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.771Z"},"containers":{"cna":{"title":"batman-adv: gw: acquire ethernet header only after skb realloc","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: gw: acquire ethernet header only after skb realloc\n\nThe pskb_may_pull() called by batadv_get_vid() could reallocate the buffer\nbehind the skb. Variables which were pointing to the old buffer need to be\nreassigned to avoid an use-after-free."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"2760b38222c8828b075802342fe3b91eb823d542","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"6c37f1166549c999ccd164b0cb6462d1ae68f8f6","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"b79884a5567bf788fb76c30832467cf6a56f3c0d","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"afac8096bde4948e3caa7e4dd733867cfbd3018e","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"e3f4325e35dd6e76b80665f3510738ce34819753","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"e6b43acd34b219b807e65096ce207b087942779d","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"916dac5f2944f63f07f7b501acbea6737dbbed0e","versionType":"git"},{"version":"6c413b1c22a2c4ef324f1c6f2c282f1ca10a93b9","status":"affected","lessThan":"77880a3be88d378d60cc1e8f8ec70430e2ed0518","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/batman-adv/gateway_client.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.14","versionType":"semver"},{"version":"5.10.261","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.212","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.178","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.145","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.97","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.40","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/batman-adv/gateway_client.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/2760b38222c8828b075802342fe3b91eb823d542"},{"url":"https://git.kernel.org/stable/c/6c37f1166549c999ccd164b0cb6462d1ae68f8f6"},{"url":"https://git.kernel.org/stable/c/b79884a5567bf788fb76c30832467cf6a56f3c0d"},{"url":"https://git.kernel.org/stable/c/afac8096bde4948e3caa7e4dd733867cfbd3018e"},{"url":"https://git.kernel.org/stable/c/e3f4325e35dd6e76b80665f3510738ce34819753"},{"url":"https://git.kernel.org/stable/c/e6b43acd34b219b807e65096ce207b087942779d"},{"url":"https://git.kernel.org/stable/c/916dac5f2944f63f07f7b501acbea6737dbbed0e"},{"url":"https://git.kernel.org/stable/c/77880a3be88d378d60cc1e8f8ec70430e2ed0518"}],"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 - The bug is hit only in batadv_interface_tx on outgoing bat0 traffic; the highest-impact path is an unauthenticated client on the same WiFi/LAN segment bridged to a batman-adv gateway node sending a crafted VLAN-tagged DHCP packet into bat0.\nAC:L - Triggering is synchronous and attacker-controlled: a VLAN-tagged DHCP discover/request shaped to force pskb_may_pull() skb reallocation deterministically hits the stale ethhdr UAF without races or victim-specific timing.\nPR:N - No privileges on the mesh router are required when a client on a bridged WiFi/LAN port injects the malicious DHCP frame; gateway-client mode is operator configuration, not an attacker privilege.\nUI:N - Exploitation requires no victim interaction beyond normal always-on mesh bridging and DHCP forwarding; the attacker only sends a malicious frame.\nS:U - Impact is kernel memory corruption and potential privilege escalation within the same kernel/host security boundary, not a cross-boundary escape such as VM or sandbox breakout.\nC:H - This is a use-after-free read: after skb reallocation, ethhdr->h_source/h_dest dereference freed skb head memory, enabling uncontrolled kernel memory disclosure and further exploitation primitives.\nI:H - UAF on skb data can corrupt routing lookups (batadv_transtable_search) and adjacent kernel heap state, providing a standard path to controlled writes and arbitrary kernel code execution.\nA:H - Reading freed skb memory via ethhdr commonly causes kernel oops/panic on the batman-adv gateway node, yielding complete loss of mesh connectivity and host availability."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-29T06:21:13.415Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"5.10.261"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"5.15.212"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"6.1.178"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.14","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-80601","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T19:18:26.470737Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T19:26:29.891Z"}}]}}}