{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2021-4442", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-08-29T09:00:39.580Z", "datePublished": "2024-08-29T09:05:37.288Z", "dateUpdated": "2026-05-11T13:44:04.320Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-11T13:44:04.320Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: add sanity tests to TCP_QUEUE_SEQ\n\nQingyu Li reported a syzkaller bug where the repro\nchanges RCV SEQ _after_ restoring data in the receive queue.\n\nmprotect(0x4aa000, 12288, PROT_READ) = 0\nmmap(0x1ffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x1ffff000\nmmap(0x20000000, 16777216, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x20000000\nmmap(0x21000000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x21000000\nsocket(AF_INET6, SOCK_STREAM, IPPROTO_IP) = 3\nsetsockopt(3, SOL_TCP, TCP_REPAIR, [1], 4) = 0\nconnect(3, {sa_family=AF_INET6, sin6_port=htons(0), sin6_flowinfo=htonl(0), inet_pton(AF_INET6, \"::1\", &sin6_addr), sin6_scope_id=0}, 28) = 0\nsetsockopt(3, SOL_TCP, TCP_REPAIR_QUEUE, [1], 4) = 0\nsendmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base=\"0x0000000000000003\\0\\0\", iov_len=20}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 20\nsetsockopt(3, SOL_TCP, TCP_REPAIR, [0], 4) = 0\nsetsockopt(3, SOL_TCP, TCP_QUEUE_SEQ, [128], 4) = 0\nrecvfrom(3, NULL, 20, 0, NULL, NULL) = -1 ECONNRESET (Connection reset by peer)\n\nsyslog shows:\n[ 111.205099] TCP recvmsg seq # bug 2: copied 80, seq 0, rcvnxt 80, fl 0\n[ 111.207894] WARNING: CPU: 1 PID: 356 at net/ipv4/tcp.c:2343 tcp_recvmsg_locked+0x90e/0x29a0\n\nThis should not be allowed. TCP_QUEUE_SEQ should only be used\nwhen queues are empty.\n\nThis patch fixes this case, and the tx path as well." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ipv4/tcp.c" ], "versions": [ { "version": "ee9952831cfd0bbe834f4a26489d7dce74582e37", "lessThan": "319f460237fc2965a80aa9a055044e1da7b3692a", "status": "affected", "versionType": "git" }, { "version": "ee9952831cfd0bbe834f4a26489d7dce74582e37", "lessThan": "3bf899438c123c444f6b644a57784dfbb6b15ad6", "status": "affected", "versionType": "git" }, { "version": "ee9952831cfd0bbe834f4a26489d7dce74582e37", "lessThan": "046f3c1c2ff450fb7ae53650e9a95e0074a61f3e", "status": "affected", "versionType": "git" }, { "version": "ee9952831cfd0bbe834f4a26489d7dce74582e37", "lessThan": "3b72d5a703842f582502d97906f17d6ee122dac2", "status": "affected", "versionType": "git" }, { "version": "ee9952831cfd0bbe834f4a26489d7dce74582e37", "lessThan": "8811f4a9836e31c14ecdf79d9f3cb7c5d463265d", "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/ipv4/tcp.c" ], "versions": [ { "version": "3.5", "status": "affected" }, { "version": "0", "lessThan": "3.5", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.181", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.106", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.24", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.11.7", "lessThanOrEqual": "5.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.12", "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": "3.5", "versionEndExcluding": "4.19.181" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.4.106" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.10.24" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.11.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/319f460237fc2965a80aa9a055044e1da7b3692a" }, { "url": "https://git.kernel.org/stable/c/3bf899438c123c444f6b644a57784dfbb6b15ad6" }, { "url": "https://git.kernel.org/stable/c/046f3c1c2ff450fb7ae53650e9a95e0074a61f3e" }, { "url": "https://git.kernel.org/stable/c/3b72d5a703842f582502d97906f17d6ee122dac2" }, { "url": "https://git.kernel.org/stable/c/8811f4a9836e31c14ecdf79d9f3cb7c5d463265d" } ], "title": "tcp: add sanity tests to TCP_QUEUE_SEQ", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2021-4442", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-09-10T15:27:19.469739Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-12T17:33:04.156Z" } } ] } }