{"id":"CVE-2023-54306","state":"PUBLISHED","title":"net: tls: avoid hanging tasks on the tx_lock","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: avoid hanging tasks on the tx_lock\n\nsyzbot sent a hung task report and Eric explains that adversarial\nreceiver may keep RWIN at 0 for a long time, so we are not guaranteed\nto make forward progress. Thread which took tx_lock and went to sleep\nmay not release tx_lock for hours. Use interruptible sleep where\npossible and reschedule the work if it can't take the lock.\n\nTesting: existing selftest passes","publishedAt":"2025-12-30T12:23:39.833Z","updatedAt":"2026-10-15T21:41:44.334Z","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":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"bde541a57b4204d0a800afbbd3d1c06c9cdb133f","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"7123a4337bf73132bbfb5437e4dc83ba864a9a1e","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"be5d5d0637fd88c18ee76024bdb22649a1de00d6","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"1f800f6aae57d2d8f63d32fff383017cbc11cf65","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"ccf1ccdc5926907befbe880b562b2a4b5f44c087","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"f3221361dc85d4de22586ce8441ec2c67b454f5d","versionType":"git"},{"version":"c8d6817345f4ba228d07380e571676405e112872","status":"affected","versionType":"git"},{"version":"5.3.11","status":"affected","lessThan":"5.4","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/tls/tls_sw.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.4","versionType":"semver"},{"version":"5.4.235","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.173","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.100","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.18","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2.5","status":"unaffected","lessThanOrEqual":"6.2.*","versionType":"semver"},{"version":"6.3","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_sw.c"]}],"references":["https://git.kernel.org/stable/c/bde541a57b4204d0a800afbbd3d1c06c9cdb133f","https://git.kernel.org/stable/c/7123a4337bf73132bbfb5437e4dc83ba864a9a1e","https://git.kernel.org/stable/c/be5d5d0637fd88c18ee76024bdb22649a1de00d6","https://git.kernel.org/stable/c/1f800f6aae57d2d8f63d32fff383017cbc11cf65","https://git.kernel.org/stable/c/ccf1ccdc5926907befbe880b562b2a4b5f44c087","https://git.kernel.org/stable/c/f3221361dc85d4de22586ce8441ec2c67b454f5d"],"weaknesses":[],"ingestedAt":"2026-10-29T20:06:42.242Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/54xxx/CVE-2023-54306.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-54306","state":"PUBLISHED","datePublished":"2025-12-30T12:23:39.833Z","dateUpdated":"2026-10-15T21:41:44.334Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-12-30T12:06:44.529Z"},"containers":{"cna":{"title":"net: tls: avoid hanging tasks on the tx_lock","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: avoid hanging tasks on the tx_lock\n\nsyzbot sent a hung task report and Eric explains that adversarial\nreceiver may keep RWIN at 0 for a long time, so we are not guaranteed\nto make forward progress. Thread which took tx_lock and went to sleep\nmay not release tx_lock for hours. Use interruptible sleep where\npossible and reschedule the work if it can't take the lock.\n\nTesting: existing selftest passes"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"bde541a57b4204d0a800afbbd3d1c06c9cdb133f","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"7123a4337bf73132bbfb5437e4dc83ba864a9a1e","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"be5d5d0637fd88c18ee76024bdb22649a1de00d6","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"1f800f6aae57d2d8f63d32fff383017cbc11cf65","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"ccf1ccdc5926907befbe880b562b2a4b5f44c087","versionType":"git"},{"version":"79ffe6087e9145d2377385cac48d0d6a6b4225a5","status":"affected","lessThan":"f3221361dc85d4de22586ce8441ec2c67b454f5d","versionType":"git"},{"version":"c8d6817345f4ba228d07380e571676405e112872","status":"affected","versionType":"git"},{"version":"5.3.11","status":"affected","lessThan":"5.4","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/tls/tls_sw.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.4","versionType":"semver"},{"version":"5.4.235","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.173","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.100","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.18","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.2.5","status":"unaffected","lessThanOrEqual":"6.2.*","versionType":"semver"},{"version":"6.3","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_sw.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/bde541a57b4204d0a800afbbd3d1c06c9cdb133f"},{"url":"https://git.kernel.org/stable/c/7123a4337bf73132bbfb5437e4dc83ba864a9a1e"},{"url":"https://git.kernel.org/stable/c/be5d5d0637fd88c18ee76024bdb22649a1de00d6"},{"url":"https://git.kernel.org/stable/c/1f800f6aae57d2d8f63d32fff383017cbc11cf65"},{"url":"https://git.kernel.org/stable/c/ccf1ccdc5926907befbe880b562b2a4b5f44c087"},{"url":"https://git.kernel.org/stable/c/f3221361dc85d4de22586ce8441ec2c67b454f5d"}],"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 - The condition that causes the tx_lock holder to sleep indefinitely is a zero TCP receive window advertised by the remote TLS peer, so a remote attacker on the network triggers the hang purely through TCP-level behavior against a kTLS-using service (nginx/OpenSSL kTLS, NFS-over-TLS tlshd, etc.). Per kernel scoring guidance, net/tls bugs driven by a remote peer are Network.\nAC:L - The attacker deterministically creates and holds the zero-window condition simply by not reading from the socket; there is no race to win, no memory-layout dependency, and no condition outside the attacker's control. A single sender is sufficient because the partial-send path itself schedules tx_work, which then blocks a kworker on the mutex.\nPR:N - The attacker is just an ordinary TLS peer of the victim service and needs no credentials on the target; for a public HTTPS/TLS endpoint the kTLS session is established with no authentication. No local account or capability on the victim system is required.\nUI:N - The victim service simply serves data over its normal kTLS send path; no administrator or user action beyond routine operation is needed. The hang occurs automatically once the attacker stalls the window.\nS:U - The impact is confined to the kernel/system that owns the vulnerable socket — blocked tasks, pinned kworkers, and a potential panic. No security boundary such as a VM, IOMMU, or sandbox is crossed.\nC:N - The defect is a lock-hold/scheduling problem with no out-of-bounds access, no use-after-free, and no uninitialized data exposure. No kernel memory contents are disclosed to the attacker.\nI:N - Nothing is written out of bounds or modified incorrectly; the record data itself is unaffected and eventually sent or discarded normally. There is no write primitive or control-flow influence available from this bug.\nA:H - The uninterruptible mutex waiters (tx_work_handler kworker, concurrent senders, and close()/exit via cancel_delayed_work_sync) become unkillable D-state tasks, tripping the hung-task watchdog and causing a kernel panic on systems with hung_task_panic=1. Even without panic, each stalled connection permanently pins a global system_wq worker (max_active 256), so repeated attacker connections starve the shared workqueue and wedge unrelated kernel work."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T09:19:05.796Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"5.4.235"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"5.10.173"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"5.15.100"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.1.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4","versionEndExcluding":"6.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.3.11"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2023-54306","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-15T21:40:10.978521Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-15T21:41:44.334Z"}}]}}}