{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-47131","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-03-04T18:12:48.840Z","datePublished":"2024-03-15T20:14:34.647Z","dateUpdated":"2025-05-04T07:04:45.261Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T07:04:45.261Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tls: Fix use-after-free after the TLS device goes down and up\n\nWhen a netdev with active TLS offload goes down, tls_device_down is\ncalled to stop the offload and tear down the TLS context. However, the\nsocket stays alive, and it still points to the TLS context, which is now\ndeallocated. If a netdev goes up, while the connection is still active,\nand the data flow resumes after a number of TCP retransmissions, it will\nlead to a use-after-free of the TLS context.\n\nThis commit addresses this bug by keeping the context alive until its\nnormal destruction, and implements the necessary fallbacks, so that the\nconnection can resume in software (non-offloaded) kTLS mode.\n\nOn the TX side tls_sw_fallback is used to encrypt all packets. The RX\nside already has all the necessary fallbacks, because receiving\nnon-decrypted packets is supported. The thing needed on the RX side is\nto block resync requests, which are normally produced after receiving\nnon-decrypted packets.\n\nThe necessary synchronization is implemented for a graceful teardown:\nfirst the fallbacks are deployed, then the driver resources are released\n(it used to be possible to have a tls_dev_resync after tls_dev_del).\n\nA new flag called TLS_RX_DEV_DEGRADED is added to indicate the fallback\nmode. It's used to skip the RX resync logic completely, as it becomes\nuseless, and some objects may be released (for example, resync_async,\nwhich is allocated and freed by the driver)."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/tls.h","net/tls/tls_device.c","net/tls/tls_device_fallback.c","net/tls/tls_main.c"],"versions":[{"version":"e8f69799810c32dd40c6724d829eccc70baad07f","lessThan":"f1d4184f128dede82a59a841658ed40d4e6d3aa2","status":"affected","versionType":"git"},{"version":"e8f69799810c32dd40c6724d829eccc70baad07f","lessThan":"0f1e6fe66977a864fe850522316f713d7b926fd9","status":"affected","versionType":"git"},{"version":"e8f69799810c32dd40c6724d829eccc70baad07f","lessThan":"c55dcdd435aa6c6ad6ccac0a4c636d010ee367a4","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/tls.h","net/tls/tls_device.c","net/tls/tls_device_fallback.c","net/tls/tls_main.c"],"versions":[{"version":"4.18","status":"affected"},{"version":"0","lessThan":"4.18","status":"unaffected","versionType":"semver"},{"version":"5.10.43","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.12.10","lessThanOrEqual":"5.12.*","status":"unaffected","versionType":"semver"},{"version":"5.13","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"5.10.43"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"5.12.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"5.13"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/f1d4184f128dede82a59a841658ed40d4e6d3aa2"},{"url":"https://git.kernel.org/stable/c/0f1e6fe66977a864fe850522316f713d7b926fd9"},{"url":"https://git.kernel.org/stable/c/c55dcdd435aa6c6ad6ccac0a4c636d010ee367a4"}],"title":"net/tls: Fix use-after-free after the TLS device goes down and up","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2021-47131","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-03-19T15:23:46.487605Z"}}}],"providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-06-04T17:14:12.171Z"}},{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-04T05:24:39.881Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/f1d4184f128dede82a59a841658ed40d4e6d3aa2","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/0f1e6fe66977a864fe850522316f713d7b926fd9","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/c55dcdd435aa6c6ad6ccac0a4c636d010ee367a4","tags":["x_transferred"]}]}]}}