{"id":"CVE-2024-44985","state":"PUBLISHED","title":"ipv6: prevent possible UAF in ip6_xmit()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: prevent possible UAF in ip6_xmit()\n\nIf skb_expand_head() returns NULL, skb has been freed\nand the associated dst/idev could also have been freed.\n\nWe must use rcu_read_lock() to prevent a possible UAF.","publishedAt":"2024-09-04T19:54:34.188Z","updatedAt":"2026-08-05T11:37:27.693Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/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":"81d626b00bdba16504eeae9cc891b18e83a9471a","status":"affected","lessThan":"b3a3d5333c13a1be57499581eab4a8fc94d57f36","versionType":"git"},{"version":"ee6b1db17f8287b615448488fc37f42bcfe9ece6","status":"affected","lessThan":"c47e022011719fc5727bca661d662303180535ba","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"975f764e96f71616b530e300c1bb2ac0ce0c2596","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"38a21c026ed2cc7232414cb166efc1923f34af17","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"124b428fe28064c809e4237b0b38e97200a8a4a8","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"fc88d6c1f2895a5775795d82ec581afdff7661d1","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"2d5ff7e339d04622d8282661df36151906d0e1c7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/ip6_output.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"5.15.166","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.107","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.48","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.10.7","status":"unaffected","lessThanOrEqual":"6.10.*","versionType":"semver"},{"version":"6.11","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/ip6_output.c"]}],"references":["https://git.kernel.org/stable/c/b3a3d5333c13a1be57499581eab4a8fc94d57f36","https://git.kernel.org/stable/c/c47e022011719fc5727bca661d662303180535ba","https://git.kernel.org/stable/c/975f764e96f71616b530e300c1bb2ac0ce0c2596","https://git.kernel.org/stable/c/38a21c026ed2cc7232414cb166efc1923f34af17","https://git.kernel.org/stable/c/124b428fe28064c809e4237b0b38e97200a8a4a8","https://git.kernel.org/stable/c/fc88d6c1f2895a5775795d82ec581afdff7661d1","https://git.kernel.org/stable/c/2d5ff7e339d04622d8282661df36151906d0e1c7","https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:07:47.831Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/44xxx/CVE-2024-44985.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-44985","state":"PUBLISHED","datePublished":"2024-09-04T19:54:34.188Z","dateUpdated":"2026-08-05T11:37:27.693Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-08-21T05:34:56.670Z"},"containers":{"cna":{"title":"ipv6: prevent possible UAF in ip6_xmit()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: prevent possible UAF in ip6_xmit()\n\nIf skb_expand_head() returns NULL, skb has been freed\nand the associated dst/idev could also have been freed.\n\nWe must use rcu_read_lock() to prevent a possible UAF."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"81d626b00bdba16504eeae9cc891b18e83a9471a","status":"affected","lessThan":"b3a3d5333c13a1be57499581eab4a8fc94d57f36","versionType":"git"},{"version":"ee6b1db17f8287b615448488fc37f42bcfe9ece6","status":"affected","lessThan":"c47e022011719fc5727bca661d662303180535ba","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"975f764e96f71616b530e300c1bb2ac0ce0c2596","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"38a21c026ed2cc7232414cb166efc1923f34af17","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"124b428fe28064c809e4237b0b38e97200a8a4a8","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"fc88d6c1f2895a5775795d82ec581afdff7661d1","versionType":"git"},{"version":"0c9f227bee11910a49e1d159abe102d06e3745d5","status":"affected","lessThan":"2d5ff7e339d04622d8282661df36151906d0e1c7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/ip6_output.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.15","versionType":"semver"},{"version":"5.15.166","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.107","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.48","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.10.7","status":"unaffected","lessThanOrEqual":"6.10.*","versionType":"semver"},{"version":"6.11","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv6/ip6_output.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/b3a3d5333c13a1be57499581eab4a8fc94d57f36"},{"url":"https://git.kernel.org/stable/c/c47e022011719fc5727bca661d662303180535ba"},{"url":"https://git.kernel.org/stable/c/975f764e96f71616b530e300c1bb2ac0ce0c2596"},{"url":"https://git.kernel.org/stable/c/38a21c026ed2cc7232414cb166efc1923f34af17"},{"url":"https://git.kernel.org/stable/c/124b428fe28064c809e4237b0b38e97200a8a4a8"},{"url":"https://git.kernel.org/stable/c/fc88d6c1f2895a5775795d82ec581afdff7661d1"},{"url":"https://git.kernel.org/stable/c/2d5ff7e339d04622d8282661df36151906d0e1c7"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - The only ip6_xmit() caller lacking a surrounding rcu_read_lock() while holding a refcounted skb dst is tcp_v6_send_response(), driven purely by inbound TCP/IPv6 packets (RST to closed ports via tcp_v6_rcv()'s no_tcp_socket path, TIME_WAIT ACKs, request-sock ACKs). A remote attacker on the internet reaches it with unsolicited TCP segments.\nAC:L - The attacker drives the vulnerable path at unbounded rate with a packet flood, and that same flood produces the GFP_ATOMIC memory pressure that makes skb_expand_head() fail, plus the CPU/scheduling pressure that widens the preemption window in the preemptible backlog-drain context; none of the required conditions lie outside attacker influence.\nPR:N - Generating a TCP RST/ACK reply to a closed or TIME_WAIT IPv6 port requires no credentials, no session, and no prior handshake — the code path is entirely pre-authentication.\nUI:N - The kernel emits the reply automatically on packet receipt; no local user or administrator action is involved.\nS:U - The freed struct inet6_dev and the resulting corruption are entirely within the kernel's own security authority, with no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The stale idev deref reads a __percpu pointer out of a freed slab object; controlling that object via heap reclaim converts the subsequent per-CPU MIB access into an attacker-directed kernel read, exposing arbitrary kernel memory.\nI:H - SNMP_INC_STATS64 performs a read-modify-write (u64_stats seqcount update plus counter add) at an address derived from the freed object's contents, yielding a controlled-address kernel write suitable for control-flow hijack once the inet6_dev allocation is groomed.\nA:H - Even unweaponized, dereferencing and incrementing through a freed inet6_dev's percpu pointer corrupts kernel memory and reliably produces an oops or panic, and the path can be re-triggered remotely at will."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T11:37:27.693Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"5.15.166"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.1.107"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.6.48"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.10.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15","versionEndExcluding":"6.11"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2024-09-10T01:05:42.699758Z","id":"CVE-2024-44985","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-09-10T01:07:00.575Z"}},{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-03T22:14:33.082Z"}}]}}}