{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2024-57974", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-57974", "idYear": 2024, "status": "PUBLISHED", "publishedAt": "2025-02-27T02:07:02.973Z", "updatedAt": "2026-10-21T12:35:44.056Z", "importedAt": "2026-10-24T01:57:20.494Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "udp: Deal with race between UDP socket address change and rehash", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nudp: Deal with race between UDP socket address change and rehash\n\nIf a UDP socket changes its local address while it's receiving\ndatagrams, as a result of connect(), there is a period during which\na lookup operation might fail to find it, after the address is changed\nbut before the secondary hash (port and address) and the four-tuple\nhash (local and remote ports and addresses) are updated.\n\nSecondary hash chains were introduced by commit 30fff9231fad (\"udp:\nbind() optimisation\") and, as a result, a rehash operation became\nneeded to make a bound socket reachable again after a connect().\n\nThis operation was introduced by commit 719f835853a9 (\"udp: add\nrehash on connect()\") which isn't however a complete fix: the\nsocket will be found once the rehashing completes, but not while\nit's pending.\n\nThis is noticeable with a socat(1) server in UDP4-LISTEN mode, and a\nclient sending datagrams to it. After the server receives the first\ndatagram (cf. _xioopen_ipdgram_listen()), it issues a connect() to\nthe address of the sender, in order to set up a directed flow.\n\nNow, if the client, running on a different CPU thread, happens to\nsend a (subsequent) datagram while the server's socket changes its\naddress, but is not rehashed yet, this will result in a failed\nlookup and a port unreachable error delivered to the client, as\napparent from the following reproducer:\n\n LEN=$(($(cat /proc/sys/net/core/wmem_default) / 4))\n dd if=/dev/urandom bs=1 count=${LEN} of=tmp.in\n\n while :; do\n \ttaskset -c 1 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc &\n \tsleep 0.1 || sleep 1\n \ttaskset -c 2 socat OPEN:tmp.in UDP4:localhost:1337,shut-null\n \twait\n done\n\nwhere the client will eventually get ECONNREFUSED on a write()\n(typically the second or third one of a given iteration):\n\n 2024/11/13 21:28:23 socat[46901] E write(6, 0x556db2e3c000, 8192): Connection refused\n\nThis issue was first observed as a seldom failure in Podman's tests\nchecking UDP functionality while using pasta(1) to connect the\ncontainer's network namespace, which leads us to a reproducer with\nthe lookup error resulting in an ICMP packet on a tap device:\n\n LOCAL_ADDR=\"$(ip -j -4 addr show|jq -rM '.[] | .addr_info[0] | select(.scope == \"global\").local')\"\n\n while :; do\n \t./pasta --config-net -p pasta.pcap -u 1337 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,trunc &\n \tsleep 0.2 || sleep 1\n \tsocat OPEN:tmp.in UDP4:${LOCAL_ADDR}:1337,shut-null\n \twait\n \tcmp tmp.in tmp.out\n done\n\nOnce this fails:\n\n tmp.in tmp.out differ: char 8193, line 29\n\nwe can finally have a look at what's going on:\n\n $ tshark -r pasta.pcap\n 1 0.000000 :: ? ff02::16 ICMPv6 110 Multicast Listener Report Message v2\n 2 0.168690 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192\n 3 0.168767 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192\n 4 0.168806 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192\n 5 0.168827 c6:47:05:8d:dc:04 ? Broadcast ARP 42 Who has 88.198.0.161? Tell 88.198.0.164\n 6 0.168851 9a:55:9a:55:9a:55 ? c6:47:05:8d:dc:04 ARP 42 88.198.0.161 is at 9a:55:9a:55:9a:55\n 7 0.168875 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192\n 8 0.168896 88.198.0.164 ? 88.198.0.161 ICMP 590 Destination unreachable (Port unreachable)\n 9 0.168926 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192\n 10 0.168959 88.198.0.161 ? 88.198.0.164 UDP 8234 60260 ? 1337 Len=8192\n 11 0.168989 88.198.0.161 ? 88.198.0.164 UDP 4138 60260 ? 1337 Len=4096\n 12 0.169010 88.198.0.161 ? 88.198.0.164 UDP 42 60260 ? 1337 Len=0\n\nOn the third datagram received, the network namespace of the container\ninitiates an ARP lookup to deliver the ICMP message.\n\nIn another variant of this reproducer, starting the client with:\n\n strace -f pasta --config-net -u 1337 socat UDP4-LISTEN:1337,null-eof OPEN:tmp.out,create,tru\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "30fff9231fad757c061285e347b33c5149c2c2e4", "status": "affected", "versionType": "git", "lessThan": "2855445a1870b8e568fb19edbd60b9c499e3dae0" }, { "version": "30fff9231fad757c061285e347b33c5149c2c2e4", "status": "affected", "versionType": "git", "lessThan": "4f8344fce91c5766d368edb0ad80142eacd805c7" }, { "version": "30fff9231fad757c061285e347b33c5149c2c2e4", "status": "affected", "versionType": "git", "lessThan": "d65d3bf309b2649d27b24efd0d8784da2d81f2a6" }, { "version": "30fff9231fad757c061285e347b33c5149c2c2e4", "status": "affected", "versionType": "git", "lessThan": "a502ea6fa94b1f7be72a24bcf9e3f5f6b7e6e90c" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.33", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.33" }, { "version": "6.6.160", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.13", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.13.2", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.13.*" }, { "version": "6.14", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }