CVE-2026-52956

HIGH
MEDIUM Priority: 0.05 BB Relevance: 75/100
Published: 2026-06-24 Modified: 2026-10-30 First seen: 2026-10-30 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: None
I: None
A: High

Description

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in __ceph_x_decrypt() In __ceph_x_decrypt(), a part of the buffer p is interpreted as a ceph_x_encrypt_header, and the magic field of this struct is accessed. This happens without any guarantee that the buffer is large enough to hold this struct. The function parameter ciphertext_len represents the length of the ciphertext to decrypt and is guaranteed to be at most the remaining size of the allocated buffer p. However, this value is not necessarily greater than sizeof(ceph_x_encrypt_header). E.g., a message frame of type FRAME_TAG_AUTH_REPLY_MORE, that is just as long to hold the ciphertext at its end with a ciphertext_len of 8 or less, can trigger an out-of-bounds memory access when accessing hdr->magic. This patch fixes the issue by adding a check to ensure that the decrypted plaintext in the buffer is large enough to represent at least the ceph_x_encrypt_header.

Weakness Classification (1)

Affected Software (13)

VendorProductVersion
Linux Linux e15fd0a11db00fc7f470a9fc804657ec3f6d04a5 < c417b7d2d1c7fdc25af24490201320e36a3cc21d
Linux Linux e15fd0a11db00fc7f470a9fc804657ec3f6d04a5 < 759053333a40c6997c2917dcd6160bfe40d2b42e
Linux Linux e15fd0a11db00fc7f470a9fc804657ec3f6d04a5 < ebc7eddf6225b87e3aae720875f9dd40cb6b1cef
Linux Linux e15fd0a11db00fc7f470a9fc804657ec3f6d04a5 < 5df268406ef38d0f92547959296577c7077dacdc
Linux Linux e15fd0a11db00fc7f470a9fc804657ec3f6d04a5 < c7e9b53aebe401970f1b5f5a01b4e021b18e8bb2
Linux Linux e15fd0a11db00fc7f470a9fc804657ec3f6d04a5 < 821365487aa58d06bda65c676ba215d506ba9768
Linux Linux 2982b9c92a66604ffb9fb2db54cf735133d1ef56
Linux Linux 4.9.6 < 4.10
Linux Linux 4.10
linux linux_kernel 4.9.6 – 4.10
linux linux_kernel 7.1
linux linux_kernel 7.1
linux linux_kernel 7.1

Bug Bounty Relevance

75 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.63%
Raw Score 0.006300
Percentile 50.2%
Date 2026-10-30

EPSS Trend

2026-10-30
0.00630
2026-10-29
0.00630

Intelligence Sources

mitre ref →
nvd ref →