{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53212", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.391Z", "datePublished": "2026-06-25T08:39:16.888Z", "dateUpdated": "2026-08-05T12:34:10.386Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:34:10.386Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nft_tunnel: fix use-after-free on object destroy\n\nnft_tunnel_obj_destroy() calls metadata_dst_free() which directly\nkfree()s the metadata_dst, ignoring the dst_entry refcount. Packets\nthat took a reference via dst_hold() in nft_tunnel_obj_eval() and\nare still queued (e.g. in a netem qdisc) are left with a dangling\npointer. When these packets are eventually dequeued, dst_release()\noperates on freed memory.\n\nReplace metadata_dst_free() with dst_release() so the metadata_dst\nis freed only after all references are dropped. The dst subsystem\nalready handles metadata_dst cleanup in dst_destroy() when\nDST_METADATA is set." } ], "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": "AV:L - The vulnerable nft_tunnel object is created, referenced, and destroyed through nf_tables netlink operations and packet processing configured locally via nftables/netdev hooks. Remote packets may help populate a queue, but exploitation requires local control of nftables transactions.\nAC:L - The attacker can set up the tunnel object/rule, arrange queued packets such as with netem, and delete the rule/object sequence under their control. No uncontrollable race or rare external condition is required.\nPR:L - nfnetlink requires CAP_NET_ADMIN in the socket network namespace, and nftables/netfilter is reachable by an unprivileged local user through user and network namespaces on typical affected systems. This is low privilege rather than real init-namespace root.\nUI:N - No victim user action is required after the attacker has local execution. The trigger is performed through attacker-issued netlink configuration and packet generation/dequeue.\nS:U - The bug corrupts kernel networking memory and can lead to local kernel privilege escalation within the same security authority. It is not a VM escape, IOMMU bypass, or other CVSS scope-changing boundary crossing.\nC:H - This is a heap use-after-free of a metadata_dst referenced from queued skbs, and similar nf_tables UAFs are exploitable for kernel memory disclosure. Following the higher-severity rule for UAFs, confidentiality impact is high.\nI:H - The freed dst/metadata object can be reclaimed and later operated on through dst_release and related networking paths, giving a plausible route to memory corruption and control-flow or arbitrary write exploitation. Following the kernel UAF guidance, integrity impact is high.\nA:H - Even without full exploitation, dequeuing packets with a dangling dst pointer can cause a kernel oops, panic, or memory-corruption crash. Availability impact is therefore high." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nft_tunnel.c" ], "versions": [ { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "349df61526d2e39decc685d246202e3e284cfe05", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "55b79b1ae42372012413ce0413181d26679b17ef", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "5e9ee18b27fde88cb6148202b33916c66693fe82", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "8767fe4079affa74314d7eb3220e700150289842", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "fda6573a46ad24f35348e024905ee5bdf729797e", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "941d7394efda5e054e2d6f3e0dd0f6a9ba19aaa3", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "f9a0e4b61054cde89a2a77845293c726cc07cc43", "status": "affected", "versionType": "git" }, { "version": "af308b94a2a4a5a27bec9028354c4df444a7c8ba", "lessThan": "c32b26aaa2f9216520a38b3f4bfeec846eb3eb8a", "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/netfilter/nft_tunnel.c" ], "versions": [ { "version": "4.19", "status": "affected" }, { "version": "0", "lessThan": "4.19", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.259", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.210", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.176", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.143", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.94", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.36", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.13", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "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": "4.19", "versionEndExcluding": "5.10.259" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "5.15.210" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "6.1.176" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "6.6.143" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "6.12.94" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "6.18.36" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "7.0.13" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/349df61526d2e39decc685d246202e3e284cfe05" }, { "url": "https://git.kernel.org/stable/c/55b79b1ae42372012413ce0413181d26679b17ef" }, { "url": "https://git.kernel.org/stable/c/5e9ee18b27fde88cb6148202b33916c66693fe82" }, { "url": "https://git.kernel.org/stable/c/8767fe4079affa74314d7eb3220e700150289842" }, { "url": "https://git.kernel.org/stable/c/fda6573a46ad24f35348e024905ee5bdf729797e" }, { "url": "https://git.kernel.org/stable/c/941d7394efda5e054e2d6f3e0dd0f6a9ba19aaa3" }, { "url": "https://git.kernel.org/stable/c/f9a0e4b61054cde89a2a77845293c726cc07cc43" }, { "url": "https://git.kernel.org/stable/c/c32b26aaa2f9216520a38b3f4bfeec846eb3eb8a" } ], "title": "netfilter: nft_tunnel: fix use-after-free on object destroy", "x_generator": { "engine": "bippy-1.2.0" } } } }