{ "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" } } ] } }