{"id":"CVE-2026-23444","state":"PUBLISHED","title":"wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure\n\nieee80211_tx_prepare_skb() has three error paths, but only two of them\nfree the skb. The first error path (ieee80211_tx_prepare() returning\nTX_DROP) does not free it, while invoke_tx_handlers() failure and the\nfragmentation check both do.\n\nAdd kfree_skb() to the first error path so all three are consistent,\nand remove the now-redundant frees in callers (ath9k, mt76,\nmac80211_hwsim) to avoid double-free.\n\nDocument the skb ownership guarantee in the function's kdoc.","publishedAt":"2026-04-03T15:15:28.464Z","updatedAt":"2026-10-19T18:35:43.925Z","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":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"905ef207d5ed99ca64adfe39fba9ac46e434327a","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"5ef8ca1c164786da24169af155c1ca1ff1353cf8","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"9a779d1f480e83720b5384adf165604e7ee226bd","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"f77b51bcee7be2bb686b5f7a2d4a1921e4bdb9f4","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"3b4d27acafaeab478fd24f79ad6e593a892828b9","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"06e769dddcbeb3baf2ce346273b53dd61fdbecf4","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"50f1b690b4868923fbd242298def2fb88662f108","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"d5ad6ab61cbd89afdb60881f6274f74328af3ee9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/ath/ath9k/channel.c","drivers/net/wireless/mediatek/mt76/scan.c","drivers/net/wireless/virtual/mac80211_hwsim.c","include/net/mac80211.h","net/mac80211/tx.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.13","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":"6.12.84","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.20","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/ath/ath9k/channel.c","drivers/net/wireless/mediatek/mt76/scan.c","drivers/net/wireless/virtual/mac80211_hwsim.c","include/net/mac80211.h","net/mac80211/tx.c"]}],"references":["https://git.kernel.org/stable/c/905ef207d5ed99ca64adfe39fba9ac46e434327a","https://git.kernel.org/stable/c/5ef8ca1c164786da24169af155c1ca1ff1353cf8","https://git.kernel.org/stable/c/9a779d1f480e83720b5384adf165604e7ee226bd","https://git.kernel.org/stable/c/f77b51bcee7be2bb686b5f7a2d4a1921e4bdb9f4","https://git.kernel.org/stable/c/3b4d27acafaeab478fd24f79ad6e593a892828b9","https://git.kernel.org/stable/c/06e769dddcbeb3baf2ce346273b53dd61fdbecf4","https://git.kernel.org/stable/c/50f1b690b4868923fbd242298def2fb88662f108","https://git.kernel.org/stable/c/d5ad6ab61cbd89afdb60881f6274f74328af3ee9","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":["CWE-401"],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23444.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23444","state":"PUBLISHED","datePublished":"2026-04-03T15:15:28.464Z","dateUpdated":"2026-10-19T18:35:43.925Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:46.019Z"},"containers":{"cna":{"title":"wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure\n\nieee80211_tx_prepare_skb() has three error paths, but only two of them\nfree the skb. The first error path (ieee80211_tx_prepare() returning\nTX_DROP) does not free it, while invoke_tx_handlers() failure and the\nfragmentation check both do.\n\nAdd kfree_skb() to the first error path so all three are consistent,\nand remove the now-redundant frees in callers (ath9k, mt76,\nmac80211_hwsim) to avoid double-free.\n\nDocument the skb ownership guarantee in the function's kdoc."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"905ef207d5ed99ca64adfe39fba9ac46e434327a","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"5ef8ca1c164786da24169af155c1ca1ff1353cf8","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"9a779d1f480e83720b5384adf165604e7ee226bd","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"f77b51bcee7be2bb686b5f7a2d4a1921e4bdb9f4","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"3b4d27acafaeab478fd24f79ad6e593a892828b9","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"06e769dddcbeb3baf2ce346273b53dd61fdbecf4","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"50f1b690b4868923fbd242298def2fb88662f108","versionType":"git"},{"version":"06be6b149f7e406bcf16098567f5a6c9f042bced","status":"affected","lessThan":"d5ad6ab61cbd89afdb60881f6274f74328af3ee9","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/ath/ath9k/channel.c","drivers/net/wireless/mediatek/mt76/scan.c","drivers/net/wireless/virtual/mac80211_hwsim.c","include/net/mac80211.h","net/mac80211/tx.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.13","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":"6.12.84","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.20","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.10","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/wireless/ath/ath9k/channel.c","drivers/net/wireless/mediatek/mt76/scan.c","drivers/net/wireless/virtual/mac80211_hwsim.c","include/net/mac80211.h","net/mac80211/tx.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/905ef207d5ed99ca64adfe39fba9ac46e434327a"},{"url":"https://git.kernel.org/stable/c/5ef8ca1c164786da24169af155c1ca1ff1353cf8"},{"url":"https://git.kernel.org/stable/c/9a779d1f480e83720b5384adf165604e7ee226bd"},{"url":"https://git.kernel.org/stable/c/f77b51bcee7be2bb686b5f7a2d4a1921e4bdb9f4"},{"url":"https://git.kernel.org/stable/c/3b4d27acafaeab478fd24f79ad6e593a892828b9"},{"url":"https://git.kernel.org/stable/c/06e769dddcbeb3baf2ce346273b53dd61fdbecf4"},{"url":"https://git.kernel.org/stable/c/50f1b690b4868923fbd242298def2fb88662f108"},{"url":"https://git.kernel.org/stable/c/d5ad6ab61cbd89afdb60881f6274f74328af3ee9"}],"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 - The vulnerable mac80211 helper is reached from local nl80211 operations such as setting wireless parameters and triggering hardware scans, not from received WiFi frames. A local attacker can drive affected scan paths through the kernel's generic netlink API.\nAC:L - The failure path can be triggered deterministically on an affected device by choosing scan parameters that produce a directed, oversized probe request with a low fragmentation threshold. No race or condition outside the attacker's control is required once the affected driver/path is available.\nPR:L - The reachable nl80211 commands are guarded by GENL_UNS_ADMIN_PERM/CAP_NET_ADMIN in the relevant network namespace, which is low privilege for CVSS purposes and can be reachable through user namespaces in plausible deployments. It does not require full init-namespace root.\nUI:N - After obtaining the needed local privileges, the attacker can issue the netlink operations directly. No separate victim action is required.\nS:U - The bug corrupts kernel networking memory within the same kernel security authority. It does not cross a VM, hypervisor, or separate security-scope boundary.\nC:H - The vulnerable failure path creates a double-free/use-after-free of an sk_buff, which is kernel heap memory corruption. Such corruption can plausibly be exploited for kernel memory disclosure, so confidentiality impact is high.\nI:H - The double-free/use-after-free can plausibly be turned into kernel heap manipulation and control-flow or data corruption. Under the required overestimate rule, this supports high integrity impact.\nA:H - Even without full exploitation, the double-free/use-after-free can trigger slab corruption, warnings, oopses, or kernel panic. Availability impact is therefore high."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:21:47.685Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"5.10.258"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"5.15.209"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.6.136"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.12.84"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.18.20"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.19.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"7.0"}]}]}],"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":"2026-10-15T01:15:05.658Z"},"x_adpType":"supplier"},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-23444","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:08:09.371784Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-401","lang":"en","type":"CWE","description":"CWE-401 Missing Release of Memory after Effective Lifetime"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T18:35:43.925Z"}}]}}}