{"id":"CVE-2026-23098","state":"PUBLISHED","title":"netrom: fix double-free in nr_route_frame()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetrom: fix double-free in nr_route_frame()\n\nIn nr_route_frame(), old_skb is immediately freed without checking if\nnr_neigh->ax25 pointer is NULL. Therefore, if nr_neigh->ax25 is NULL,\nthe caller function will free old_skb again, causing a double-free bug.\n\nTherefore, to prevent this, we need to modify it to check whether\nnr_neigh->ax25 is NULL before freeing old_skb.","publishedAt":"2026-02-04T16:08:20.692Z","updatedAt":"2026-08-05T12:20:15.261Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"25aab6bfc31017a7e52035b99aef5c2b6bde8ffb","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6e0110ea90313b7c0558a0b77038274a6821caf8","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"7c48fdf2d1349bb54815b56fb012b9d577707708","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"bd8955337e3764f912f49b360e176d8aaecf7016","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"94d1a8bd08af1f4cc345c5c29f5db1ea72b8bb8c","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9f5fa78d9980fe75a69835521627ab7943cb3d67","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"ba1096c315283ee3292765f6aea4cca15816c4f7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/netrom/nr_route.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"5.10.249","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.199","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.162","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.122","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.68","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.8","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/netrom/nr_route.c"]}],"references":["https://git.kernel.org/stable/c/25aab6bfc31017a7e52035b99aef5c2b6bde8ffb","https://git.kernel.org/stable/c/6e0110ea90313b7c0558a0b77038274a6821caf8","https://git.kernel.org/stable/c/7c48fdf2d1349bb54815b56fb012b9d577707708","https://git.kernel.org/stable/c/bd8955337e3764f912f49b360e176d8aaecf7016","https://git.kernel.org/stable/c/94d1a8bd08af1f4cc345c5c29f5db1ea72b8bb8c","https://git.kernel.org/stable/c/9f5fa78d9980fe75a69835521627ab7943cb3d67","https://git.kernel.org/stable/c/ba1096c315283ee3292765f6aea4cca15816c4f7"],"weaknesses":[],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23098.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23098","state":"PUBLISHED","datePublished":"2026-02-04T16:08:20.692Z","dateUpdated":"2026-08-05T12:20:15.261Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:45.964Z"},"containers":{"cna":{"title":"netrom: fix double-free in nr_route_frame()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetrom: fix double-free in nr_route_frame()\n\nIn nr_route_frame(), old_skb is immediately freed without checking if\nnr_neigh->ax25 pointer is NULL. Therefore, if nr_neigh->ax25 is NULL,\nthe caller function will free old_skb again, causing a double-free bug.\n\nTherefore, to prevent this, we need to modify it to check whether\nnr_neigh->ax25 is NULL before freeing old_skb."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"25aab6bfc31017a7e52035b99aef5c2b6bde8ffb","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"6e0110ea90313b7c0558a0b77038274a6821caf8","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"7c48fdf2d1349bb54815b56fb012b9d577707708","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"bd8955337e3764f912f49b360e176d8aaecf7016","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"94d1a8bd08af1f4cc345c5c29f5db1ea72b8bb8c","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"9f5fa78d9980fe75a69835521627ab7943cb3d67","versionType":"git"},{"version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","status":"affected","lessThan":"ba1096c315283ee3292765f6aea4cca15816c4f7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/netrom/nr_route.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.12","versionType":"semver"},{"version":"5.10.249","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.199","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.162","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.122","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.68","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.8","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/netrom/nr_route.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/25aab6bfc31017a7e52035b99aef5c2b6bde8ffb"},{"url":"https://git.kernel.org/stable/c/6e0110ea90313b7c0558a0b77038274a6821caf8"},{"url":"https://git.kernel.org/stable/c/7c48fdf2d1349bb54815b56fb012b9d577707708"},{"url":"https://git.kernel.org/stable/c/bd8955337e3764f912f49b360e176d8aaecf7016"},{"url":"https://git.kernel.org/stable/c/94d1a8bd08af1f4cc345c5c29f5db1ea72b8bb8c"},{"url":"https://git.kernel.org/stable/c/9f5fa78d9980fe75a69835521627ab7943cb3d67"},{"url":"https://git.kernel.org/stable/c/ba1096c315283ee3292765f6aea4cca15816c4f7"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:A - AX.25 is a link-layer protocol reachable via radio links or BPQ Ethernet (same LAN segment). NET/ROM runs on top of AX.25 and while it provides routing across hops, the entry point requires adjacency to the AX.25 network.\nAC:L - The double-free triggers deterministically when ax25_send_frame() returns NULL due to the neighbor device lacking AX.25 configuration. Syzbot reproduced this reliably, and no race condition or special memory layout is required.\nPR:N - No authentication or privilege checks exist on the AX.25 receive path. Any station on the AX.25 network can send frames that are processed through the vulnerable code path without credentials.\nUI:N - The vulnerability triggers during normal packet processing when a NET/ROM routing frame is received. No victim action is required.\nS:U - This is a standard kernel memory corruption bug that does not cross security boundaries like VM or IOMMU isolation.\nC:H - A double-free on sk_buff gives the attacker control over freed heap objects, enabling arbitrary memory read through heap spraying techniques.\nI:H - The double-free enables heap corruption and arbitrary write primitives through slab allocator manipulation, potentially leading to kernel code execution.\nA:H - The double-free causes immediate kernel memory corruption leading to a crash, panic, or oops, providing reliable denial of service."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:20:15.261Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.10.249"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"5.15.199"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.1.162"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.6.122"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.12.68"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.18.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.12","versionEndExcluding":"6.19"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}