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CVE-2024-56563 (GCVE-0-2024-56563)

Vulnerability from cvelistv5 – Published: 2024-12-27 14:23 – Updated: 2026-08-05 11:45
VLAI
Title
ceph: fix cred leak in ceph_mds_check_access()
Summary
In the Linux kernel, the following vulnerability has been resolved: ceph: fix cred leak in ceph_mds_check_access() get_current_cred() increments the reference counter, but the put_cred() call was missing.
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 596afb0b8933ba6ed7227adcc538db26feb25c74 , < e3d1c9e2b811f13bdbbb962c2b17a6091c28522c (git)
Affected: 596afb0b8933ba6ed7227adcc538db26feb25c74 , < c5cf420303256dcd6ff175643e9e9558543c2047 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.10
Unaffected: 0 , < 6.10 (semver)
Unaffected: 6.12.4 , ≤ 6.12.* (semver)
Unaffected: 6.13 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website

{
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              "value": "AV:L - The leak is triggered by ordinary local VFS syscalls (`open`, `creat`, `unlink`, `chmod`, `truncate`) issued against a mounted CephFS; no network peer input reaches the vulnerable function directly.\nAC:L - The missing `put_cred()` is unconditional \u2014 every single call to `ceph_mds_check_access()` leaks a reference with no race, timing window, or special configuration required, so a trivial loop drives the leak deterministically.\nPR:L - Any unprivileged local user with access to a path on an already-mounted CephFS can trigger it; the call sites in `ceph_open()`/`ceph_atomic_open()`/`ceph_unlink()`/`__ceph_setattr() ` are reached before any capability or auth gate.\nUI:N - No action by another user is needed \u2014 the attacker triggers the leak entirely on their own via normal file operations on the existing mount.\nS:U - The leaked credentials and any resulting corruption stay within the kernel\u0027s own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The leaked object is `struct cred`, incremented through an unchecked `atomic_long_add()` with no `refcount_t` saturation; on 32-bit builds the counter wraps at 2^32, freeing a live credential structure and yielding a use-after-free read primitive over uid/gid/capability fields.\nI:H - The same credential refcount imbalance/overflow permits a freed `cred` to be reallocated and overwritten by attacker-controlled heap content \u2014 the classic CVE-2016-0728-style path to arbitrary modification of `cap_effective`/`euid` and full local privilege escalation.\nA:H - Each operation permanently pins a `cred` plus its `user_struct`, `user_namespace`, `ucounts`, `group_info` and keyrings, so an unprivileged loop produces an unbounded, unreclaimable kernel memory leak ending in OOM, and the 32-bit refcount wrap causes an outright UAF crash."
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    "datePublished": "2024-12-27T14:23:07.854Z",
    "dateReserved": "2024-12-27T14:03:05.994Z",
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          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ceph: se corrige la p\u00e9rdida de credenciales en ceph_mds_check_access(). get_current_cred() incrementa el contador de referencia, pero faltaba la llamada put_cred()."
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        ],
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        "lastModified": "2026-08-04T11:22:11.233",
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}



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