CVE-2026-52958

Description

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in osdmap_decode() When decoding osd_state and osd_weight from an incoming osdmap in osdmap_decode(), both are decoded for each osd, i.e., map->max_osd times. The ceph_decode_need() check only accounts for sizeof(*map->osd_weight) once. This can potentially result in an out-of-bounds memory access if the incoming message is corrupted such that the max_osd value exceeds the actual content of the osdmap message. This patch fixes the issue by changing the corresponding part in the ceph_decode_need() check to account for map->max_osd*sizeof(*map->osd_weight).

CVSS v3.1 Score

9.1

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

EPSS — Exploit Prediction

0.0054

Probability of exploitation

0.42%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/0d2dd7e6bb74fd7712aa73457a4a821906c6863a https://git.kernel.org/stable/c/35d0ed82d03e5ee77ea4f31f20e29562a7721649 https://git.kernel.org/stable/c/36a79759a288961b1ff28a68ec2d1f56f6848098 https://git.kernel.org/stable/c/3f2575bb7f955d42569d96c3e04fa958a0dcf4b4 https://git.kernel.org/stable/c/48df98d12b15360cd56af5c1f460307b340c1197 https://git.kernel.org/stable/c/8713bbc4b2b9ad78f803978e54b7e49dd21bd9be https://git.kernel.org/stable/c/e7187f33c02488697ec0d01d82bf7a3f8deaba8f https://git.kernel.org/stable/c/ee933694645dac062d65fc2743f92bc06fa0db6b

Frequently Asked Questions

What is CVE-2026-52958? +

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in osdmap_decode() When decoding osd_state and osd_weight from an incoming osdmap in osdmap_decode(), both are decoded for each osd, i.e., map->max_osd times. The ceph_decode_need() check only accounts for sizeof(*map->osd_weight) once. This can potentially result in an out-of-bounds memory access if the incoming message is corrupted such that the max_osd value exceeds the actual content of the osdmap message. This patch fixes the issue by changing the corresponding part in the ceph_decode_need() check to account for map->max_osd*sizeof(*map->osd_weight). It has a CVSS v3.1 base score of 9.1 (CRITICAL).

How severe is CVE-2026-52958? +

CVE-2026-52958 has a CVSS v3.1 score of 9.1 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0054, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-52958? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.