{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-21703", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T08:45:45.751Z", "datePublished": "2025-02-18T14:37:44.261Z", "dateUpdated": "2026-08-05T11:53:46.285Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:53:46.285Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetem: Update sch->q.qlen before qdisc_tree_reduce_backlog()\n\nqdisc_tree_reduce_backlog() notifies parent qdisc only if child\nqdisc becomes empty, therefore we need to reduce the backlog of the\nchild qdisc before calling it. Otherwise it would miss the opportunity\nto call cops->qlen_notify(), in the case of DRR, it resulted in UAF\nsince DRR uses ->qlen_notify() to maintain its active list." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "UAF in netem/DRR qdisc interaction. qdisc_tree_reduce_backlog() called before qlen update misses DRR qlen_notify, leaving freed class on active list. Exploitable for privilege escalation from unprivileged user namespaces." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_netem.c" ], "versions": [ { "version": "83c6ab12f08dcc09d4c5ac86fdb89736b28f1d31", "lessThan": "e395fec75ac2dbffc99b4bce57b7f1f3c5449f2c", "status": "affected", "versionType": "git" }, { "version": "216509dda290f6db92c816dd54b83c1df9da9e76", "lessThan": "7f31d74fcc556a9166b1bb20515542de7bb939d1", "status": "affected", "versionType": "git" }, { "version": "c2047b0e216c8edce227d7c42f99ac2877dad0e4", "lessThan": "98a2c685293aae122f688cde11d9334dddc5d207", "status": "affected", "versionType": "git" }, { "version": "10df49cfca73dfbbdb6c4150d859f7e8926ae427", "lessThan": "7b79ca9a1de6a428d486ff52fb3d602321c08f55", "status": "affected", "versionType": "git" }, { "version": "3824c5fad18eeb7abe0c4fc966f29959552dca3e", "lessThan": "1f8e3f4a4b8b90ad274dfbc66fc7d55cb582f4d5", "status": "affected", "versionType": "git" }, { "version": "356078a5c55ec8d2061fcc009fb8599f5b0527f9", "lessThan": "6312555249082d6d8cc5321ff725df05482d8b83", "status": "affected", "versionType": "git" }, { "version": "f8d4bc455047cf3903cd6f85f49978987dbb3027", "lessThan": "839ecc583fa00fab785fde1c85a326743657fd32", "status": "affected", "versionType": "git" }, { "version": "f8d4bc455047cf3903cd6f85f49978987dbb3027", "lessThan": "638ba5089324796c2ee49af10427459c2de35f71", "status": "affected", "versionType": "git" }, { "version": "5.4.288", "lessThan": "5.4.291", "status": "affected", "versionType": "semver" }, { "version": "5.10.232", "lessThan": "5.10.235", "status": "affected", "versionType": "semver" }, { "version": "5.15.175", "lessThan": "5.15.179", "status": "affected", "versionType": "semver" }, { "version": "6.1.121", "lessThan": "6.1.129", "status": "affected", "versionType": "semver" }, { "version": "6.6.67", "lessThan": "6.6.78", "status": "affected", "versionType": "semver" }, { "version": "6.12.6", "lessThan": "6.12.14", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_netem.c" ], "versions": [ { "version": "6.13", "status": "affected" }, { "version": "0", "lessThan": "6.13", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.291", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.235", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.179", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.129", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.78", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.14", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.13.3", "lessThanOrEqual": "6.13.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.14", "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": "5.4.288", "versionEndExcluding": "5.4.291" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.232", "versionEndExcluding": "5.10.235" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.175", "versionEndExcluding": "5.15.179" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.121", "versionEndExcluding": "6.1.129" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.67", "versionEndExcluding": "6.6.78" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12.6", "versionEndExcluding": "6.12.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.13.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.14" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/e395fec75ac2dbffc99b4bce57b7f1f3c5449f2c" }, { "url": "https://git.kernel.org/stable/c/7f31d74fcc556a9166b1bb20515542de7bb939d1" }, { "url": "https://git.kernel.org/stable/c/98a2c685293aae122f688cde11d9334dddc5d207" }, { "url": "https://git.kernel.org/stable/c/7b79ca9a1de6a428d486ff52fb3d602321c08f55" }, { "url": "https://git.kernel.org/stable/c/1f8e3f4a4b8b90ad274dfbc66fc7d55cb582f4d5" }, { "url": "https://git.kernel.org/stable/c/6312555249082d6d8cc5321ff725df05482d8b83" }, { "url": "https://git.kernel.org/stable/c/839ecc583fa00fab785fde1c85a326743657fd32" }, { "url": "https://git.kernel.org/stable/c/638ba5089324796c2ee49af10427459c2de35f71" } ], "title": "netem: Update sch->q.qlen before qdisc_tree_reduce_backlog()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH" } }, { "other": { "type": "ssvc", "content": { "id": "CVE-2025-21703", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2025-02-18T15:38:37.163490Z" } } } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free" } ] } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-02-18T15:46:03.772Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T19:35:52.049Z" } } ] } }