{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72330", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.919Z", "datePublished": "2026-08-15T05:55:40.555Z", "dateUpdated": "2026-08-17T05:42:52.302Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:42:52.302Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tls: Consume empty data records in tls_sw_read_sock()\n\nA peer may send a zero-length TLS application_data record; TLS 1.3\nexplicitly permits these as a traffic-analysis countermeasure (RFC\n8446, Section 5.1). After decryption such a record has full_len ==\n0. tls_sw_read_sock() hands it to the read_actor, which has no\npayload to consume and returns zero. The loop treats a zero return\nas backpressure (used <= 0), requeues the skb at the head of\nrx_list, and stops. rx_list is serviced head-first on the next\ncall, so the empty record is dequeued, fails the same way, and is\nrequeued again; every later record on the connection is blocked\nbehind it.\n\ntls_sw_recvmsg() does not stall on this: a zero-length data record\ncopies nothing and falls through to consume_skb(). Mirror that in\nthe read_sock() path by recognizing an empty data record before\nthe actor runs, consuming it, and continuing." } ], "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 sends zero-length TLS 1.3 application_data records over TCP; they are decrypted in the kTLS software RX path and processed in tls_sw_read_sock(), reachable from network-facing consumers such as NVMe-over-TCP host I/O via sock->ops->read_sock.\nAC:L - After a normal TLS handshake, sending a standards-compliant zero-length application_data record reliably reproduces the stall; no races, special memory layout, or rare timing are required.\nPR:N - Exploitation requires only being the remote TLS peer on an established kTLS connection (e.g. a malicious NVMe-oF target); no local account, capability, namespace, or administrator privileges on the victim host are needed.\nUI:N - No victim user action beyond the system maintaining its normal encrypted network connection; the attacker triggers the flaw by sending protocol-valid TLS records.\nS:U - Impact is confined to stalling the affected TLS/kTLS connection and its dependent service I/O; it does not cross a security boundary such as guest-to-host escape or sandbox breakout.\nC:N - The flaw is a receive-path logic error that requeues an empty skb indefinitely; there is no out-of-bounds access, use-after-free, or other memory corruption that could disclose kernel or application data.\nI:N - The bug does not modify kernel memory, credentials, or application data; it only prevents forward progress on the stalled connection by blocking consumption of subsequent decrypted records.\nA:H - The empty record is permanently requeued at the head of rx_list, creating a repeatable deadlock that blocks all later traffic on the connection and can hang NVMe-over-TCP (or similar read_sock) I/O until the connection is torn down." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/tls/tls_sw.c" ], "versions": [ { "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945", "lessThan": "0867b0f2513ebc1c475af9898c97f4772a68d964", "status": "affected", "versionType": "git" }, { "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945", "lessThan": "c6b440cf766a557b08d25f1b571b3d57d039686e", "status": "affected", "versionType": "git" }, { "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945", "lessThan": "e8a4c9fc437b16aef38f86ce3275677e36924259", "status": "affected", "versionType": "git" }, { "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945", "lessThan": "ebc295ce343600c2d60c1e1e0c5d192080217457", "status": "affected", "versionType": "git" }, { "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945", "lessThan": "3be28e2c9cd0230cb51fd4967df095273afd3848", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/tls/tls_sw.c" ], "versions": [ { "version": "6.6", "status": "affected" }, { "version": "0", "lessThan": "6.6", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "6.6", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/0867b0f2513ebc1c475af9898c97f4772a68d964" }, { "url": "https://git.kernel.org/stable/c/c6b440cf766a557b08d25f1b571b3d57d039686e" }, { "url": "https://git.kernel.org/stable/c/e8a4c9fc437b16aef38f86ce3275677e36924259" }, { "url": "https://git.kernel.org/stable/c/ebc295ce343600c2d60c1e1e0c5d192080217457" }, { "url": "https://git.kernel.org/stable/c/3be28e2c9cd0230cb51fd4967df095273afd3848" } ], "title": "net/tls: Consume empty data records in tls_sw_read_sock()", "x_generator": { "engine": "bippy-1.2.0" } } } }