{"id":"CVE-2026-52974","state":"PUBLISHED","title":"net: tls: fix strparser anchor skb leak on offload RX setup failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: fix strparser anchor skb leak on offload RX setup failure\n\nWhen tls_set_device_offload_rx() fails at tls_dev_add(), the error path\ncalls tls_sw_free_resources_rx() to clean up the SW context that was\ninitialized by tls_set_sw_offload(). This function calls\ntls_sw_release_resources_rx() (which stops the strparser via\ntls_strp_stop()) and tls_sw_free_ctx_rx() (which kfrees the context),\nbut never frees the anchor skb that was allocated by alloc_skb(0) in\ntls_strp_init().\n\nNote that tls_sw_free_resources_rx() is exclusively used for this\n\"failed to start offload\" code path, there's no other caller.\n\nThe leak did not exist before commit 84c61fe1a75b (\"tls: rx: do not use\nthe standard strparser\"), because the standard strparser doesn't try\nto pre-allocate an skb.\n\nThe normal close path in tls_sk_proto_close() handles cleanup by calling\ntls_sw_strparser_done() (which calls tls_strp_done()) after dropping\nthe socket lock, because tls_strp_done() does cancel_work_sync() and\nthe strparser work handler takes the socket lock.","publishedAt":"2026-06-24T16:28:51.826Z","updatedAt":"2026-10-19T19:47:11.322Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"0c9f399b37ce22a5ed94cc51f03ed07ac7f38e32","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"688f12aa44511dd57e448eb670075c6302ad1dc1","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"3c405dfa9619e506e75b8e41f8b29a5b99731877","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"9c54e76f8d6eb11735918777ef0e0509e089557d","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"bd07fe6c38b9e44ff3fc02692a53f095c5cc9afc","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"58689498ca3384851145a754dbb1d8ed1cf9fb54","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/tls/tls.h","net/tls/tls_strp.c","net/tls/tls_sw.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.141","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","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/tls/tls.h","net/tls/tls_strp.c","net/tls/tls_sw.c"]}],"references":["https://git.kernel.org/stable/c/0c9f399b37ce22a5ed94cc51f03ed07ac7f38e32","https://git.kernel.org/stable/c/688f12aa44511dd57e448eb670075c6302ad1dc1","https://git.kernel.org/stable/c/3c405dfa9619e506e75b8e41f8b29a5b99731877","https://git.kernel.org/stable/c/9c54e76f8d6eb11735918777ef0e0509e089557d","https://git.kernel.org/stable/c/bd07fe6c38b9e44ff3fc02692a53f095c5cc9afc","https://git.kernel.org/stable/c/58689498ca3384851145a754dbb1d8ed1cf9fb54"],"weaknesses":["CWE-401"],"ingestedAt":"2026-10-29T20:12:16.098Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/52xxx/CVE-2026-52974.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-52974","state":"PUBLISHED","datePublished":"2026-06-24T16:28:51.826Z","dateUpdated":"2026-10-19T19:47:11.322Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-06-09T07:44:35.375Z"},"containers":{"cna":{"title":"net: tls: fix strparser anchor skb leak on offload RX setup failure","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: fix strparser anchor skb leak on offload RX setup failure\n\nWhen tls_set_device_offload_rx() fails at tls_dev_add(), the error path\ncalls tls_sw_free_resources_rx() to clean up the SW context that was\ninitialized by tls_set_sw_offload(). This function calls\ntls_sw_release_resources_rx() (which stops the strparser via\ntls_strp_stop()) and tls_sw_free_ctx_rx() (which kfrees the context),\nbut never frees the anchor skb that was allocated by alloc_skb(0) in\ntls_strp_init().\n\nNote that tls_sw_free_resources_rx() is exclusively used for this\n\"failed to start offload\" code path, there's no other caller.\n\nThe leak did not exist before commit 84c61fe1a75b (\"tls: rx: do not use\nthe standard strparser\"), because the standard strparser doesn't try\nto pre-allocate an skb.\n\nThe normal close path in tls_sk_proto_close() handles cleanup by calling\ntls_sw_strparser_done() (which calls tls_strp_done()) after dropping\nthe socket lock, because tls_strp_done() does cancel_work_sync() and\nthe strparser work handler takes the socket lock."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"0c9f399b37ce22a5ed94cc51f03ed07ac7f38e32","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"688f12aa44511dd57e448eb670075c6302ad1dc1","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"3c405dfa9619e506e75b8e41f8b29a5b99731877","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"9c54e76f8d6eb11735918777ef0e0509e089557d","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"bd07fe6c38b9e44ff3fc02692a53f095c5cc9afc","versionType":"git"},{"version":"84c61fe1a75b4255df1e1e7c054c9e6d048da417","status":"affected","lessThan":"58689498ca3384851145a754dbb1d8ed1cf9fb54","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/tls/tls.h","net/tls/tls_strp.c","net/tls/tls_sw.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.0","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.0","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.141","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.91","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.33","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.0.10","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/tls/tls.h","net/tls/tls_strp.c","net/tls/tls_sw.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/0c9f399b37ce22a5ed94cc51f03ed07ac7f38e32"},{"url":"https://git.kernel.org/stable/c/688f12aa44511dd57e448eb670075c6302ad1dc1"},{"url":"https://git.kernel.org/stable/c/3c405dfa9619e506e75b8e41f8b29a5b99731877"},{"url":"https://git.kernel.org/stable/c/9c54e76f8d6eb11735918777ef0e0509e089557d"},{"url":"https://git.kernel.org/stable/c/bd07fe6c38b9e44ff3fc02692a53f095c5cc9afc"},{"url":"https://git.kernel.org/stable/c/58689498ca3384851145a754dbb1d8ed1cf9fb54"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:N - A remote TLS peer can plausibly trigger this through a network-facing kTLS-enabled service that installs TLS_RX state after handshake on a TLS RX offload-capable NIC. The direct kernel path is setsockopt-driven, but the vulnerable subsystem is kTLS receive/offload setup for network connections and can be reached per remote connection.\nAC:L - There is no race or fragile timing requirement; the attacker can repeatedly drive RX state setup and can plausibly force tls_dev_add() failure via unsupported TLS 1.2 RX offload parameters or exhausted offload resources. The required offload-capable deployment is a reasonable server scenario for this subsystem.\nPR:N - In the network-facing kTLS service scenario, the attacker needs no local account or prior authentication to initiate TLS connections that cause the service to install RX state. Any application-level authentication would occur after the connection setup path.\nUI:N - No victim user action is required beyond the target service automatically handling incoming TLS connections. The attacker can repeat the trigger by opening connections.\nS:U - The impact remains within the kernel and network stack security authority. There is no VM escape, IOMMU bypass, or cross-scope boundary crossing.\nC:N - The bug leaks an internal zero-length anchor skb object by losing its reference; it does not expose kernel memory contents to the attacker. No read primitive or information disclosure was identified.\nI:N - The issue is a missing cleanup in an error path and does not corrupt memory or modify attacker-chosen kernel data. No write primitive or control-flow impact was identified.\nA:H - The leaked skb is kernel memory and the failing offload setup path can be triggered repeatedly, allowing unbounded memory consumption. Related strparser skb leak precedent treats repeatable network-triggered memory exhaustion as high availability impact."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:32:16.022Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.6.141"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.12.91"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"6.18.33"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.0.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0","versionEndExcluding":"7.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-52974","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-16T15:23:49.246897Z"}}}],"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":"2026-10-19T19:47:11.322Z"}}]}}}