{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38273","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T04:51:23.998Z","datePublished":"2025-07-10T07:41:54.415Z","dateUpdated":"2026-08-05T12:00:54.344Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:00:54.344Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tipc: fix refcount warning in tipc_aead_encrypt\n\nsyzbot reported a refcount warning [1] caused by calling get_net() on\na network namespace that is being destroyed (refcount=0). This happens\nwhen a TIPC discovery timer fires during network namespace cleanup.\n\nThe recently added get_net() call in commit e279024617134 (\"net/tipc:\nfix slab-use-after-free Read in tipc_aead_encrypt_done\") attempts to\nhold a reference to the network namespace. However, if the namespace\nis already being destroyed, its refcount might be zero, leading to the\nuse-after-free warning.\n\nReplace get_net() with maybe_get_net(), which safely checks if the\nrefcount is non-zero before incrementing it. If the namespace is being\ndestroyed, return -ENODEV early, after releasing the bearer reference.\n\n[1]: https://lore.kernel.org/all/68342b55.a70a0220.253bc2.0091.GAE@google.com/T/#m12019cf9ae77e1954f666914640efa36d52704a2"}],"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 trigger is a purely local sequence — create a network namespace, enable a TIPC bearer, install an AEAD key via TIPC genetlink, then tear the namespace down — with no remote peer or packet required. `init_net`'s refcount never reaches zero, so the bug is only reachable through locally-driven netns destruction.\nAC:L - The attacker controls both sides of the race: they start the discovery timer (which re-arms at least every second while the bearer is up) and they choose when to destroy the namespace, and `cleanup_net()`'s window (batched teardown, `pernet_ops_rwsem`, `rcu_barrier()`) routinely exceeds that interval. The sequence is scriptable in a tight loop, and unlike the parent UAF no cryptd/SIMD fallback is needed since `get_net()` runs on every encrypt.\nPR:L - TIPC bearer-enable and key-set are gated on CAP_NET_ADMIN, but every op in net/tipc/netlink.c uses `GENL_UNS_ADMIN_PERM`, which is satisfied by CAP_NET_ADMIN in a user-namespace-owned netns — an unprivileged user reaches all of it via `unshare -Urn`. No real root in the initial namespace is required.\nUI:N - The entire sequence is performed by the attacker's own process; the discovery timer fires on its own from softirq context. No victim action or interaction of any kind is involved.\nS:U - The corrupted refcount, the freed `tipc_crypto`, and the freed `struct net` all belong to the kernel's own security authority. There is no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The failed reference acquisition re-opens the slab use-after-free it was meant to close: `tipc_aead_encrypt_done()` runs from the cryptd workqueue against a `tipc_crypto` already freed by `tipc_crypto_stop()` and a `struct net` freed by `cleanup_net()`, reading `tx->stats`, `b->up`, and `tx_ctx` out of reallocated slab memory. A UAF read on attacker-groomable heap is treated as arbitrary kernel memory disclosure.\nI:H - The same window yields write primitives on freed memory — `this_cpu_inc(tx->stats->stat[...])` through a freed per-CPU pointer and `put_net()`'s atomic decrement on the freed `struct net` — which is heap-sprayable into an attacker-chosen object. Additionally the refcount is force-set to `REFCOUNT_SATURATED`, corrupting namespace lifetime accounting.\nA:H - The immediate result is a `WARN_ONCE` splat, which is an outright kernel panic on the many hardened, cloud, and syzkaller-style deployments running `panic_on_warn=1`, and the subsequent use-after-free reliably oopses even when not weaponized. The whole sequence is repeatable in a loop by an unprivileged local user."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/tipc/crypto.c"],"versions":[{"version":"d42ed4de6aba232d946d20653a70f79158a6535b","lessThan":"445d59025d76d0638b03110f8791d5b89ed5162d","status":"affected","versionType":"git"},{"version":"f5c2c4eaaa5a8e7e0685ec031d480e588e263e59","lessThan":"e0b11227c4e8eb4bdf1b86aa8f0f3abb24e0f029","status":"affected","versionType":"git"},{"version":"b8fcae6d2e93c54cacb8f579a77d827c1c643eb5","lessThan":"307391e8fe70401a6d39ecc9978e13c2c0cdf81f","status":"affected","versionType":"git"},{"version":"b19fc1d0be3c3397e5968fe2627f22e7f84673b1","lessThan":"acab7ca5ff19889b80a8ee7dec220ee1a96dede9","status":"affected","versionType":"git"},{"version":"689a205cd968a1572ab561b0c4c2d50a10e9d3b0","lessThan":"c762fc79d710d676b793f9d98b1414efe6eb51e6","status":"affected","versionType":"git"},{"version":"e279024617134c94fd3e37470156534d5f2b3472","lessThan":"9ff60e0d9974dccf24e89bcd3ee7933e538d929f","status":"affected","versionType":"git"},{"version":"e279024617134c94fd3e37470156534d5f2b3472","lessThan":"f29ccaa07cf3d35990f4d25028cc55470d29372b","status":"affected","versionType":"git"},{"version":"4a0fddc2c0d5c28aec8c262ad4603be0bef1938c","status":"affected","versionType":"git"},{"version":"5.10.238","lessThan":"5.10.239","status":"affected","versionType":"semver"},{"version":"5.15.185","lessThan":"5.15.186","status":"affected","versionType":"semver"},{"version":"6.1.141","lessThan":"6.1.142","status":"affected","versionType":"semver"},{"version":"6.6.93","lessThan":"6.6.94","status":"affected","versionType":"semver"},{"version":"6.12.31","lessThan":"6.12.34","status":"affected","versionType":"semver"},{"version":"6.14.9","lessThan":"6.15","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/tipc/crypto.c"],"versions":[{"version":"6.15","status":"affected"},{"version":"0","lessThan":"6.15","status":"unaffected","versionType":"semver"},{"version":"5.10.239","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.186","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.142","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.94","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.34","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.15.3","lessThanOrEqual":"6.15.*","status":"unaffected","versionType":"semver"},{"version":"6.16","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":"5.10.238","versionEndExcluding":"5.10.239"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.185","versionEndExcluding":"5.15.186"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.141","versionEndExcluding":"6.1.142"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.93","versionEndExcluding":"6.6.94"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.12.31","versionEndExcluding":"6.12.34"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"6.15.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.15","versionEndExcluding":"6.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14.9"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/445d59025d76d0638b03110f8791d5b89ed5162d"},{"url":"https://git.kernel.org/stable/c/e0b11227c4e8eb4bdf1b86aa8f0f3abb24e0f029"},{"url":"https://git.kernel.org/stable/c/307391e8fe70401a6d39ecc9978e13c2c0cdf81f"},{"url":"https://git.kernel.org/stable/c/acab7ca5ff19889b80a8ee7dec220ee1a96dede9"},{"url":"https://git.kernel.org/stable/c/c762fc79d710d676b793f9d98b1414efe6eb51e6"},{"url":"https://git.kernel.org/stable/c/9ff60e0d9974dccf24e89bcd3ee7933e538d929f"},{"url":"https://git.kernel.org/stable/c/f29ccaa07cf3d35990f4d25028cc55470d29372b"}],"title":"net: tipc: fix refcount warning in tipc_aead_encrypt","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T17:36:08.105Z"}}]}}