CVEPublished 2025-09-23Modified 2026-07-301 article on news5 live referencesNVD data

CVE-2025-39880Linux · Linux_kernel

Vulnerability data via NVD (ingested)

CVSS v3.1
9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS percentile
4
Exploit Prediction Scoring System · top 96% of all CVEs
Description

In the Linux kernel, the following vulnerability has been resolved: libceph: fix invalid accesses to ceph_connection_v1_info There is a place where generic code in messenger.c is reading and another place where it is writing to con->v1 union member without checking that the union member is active (i.e. msgr1 is in use). On 64-bit systems, con->v1.auth_retry overlaps with con->v2.out_iter, so such a read is almost guaranteed to return a bogus value instead of 0 when msgr2 is in use. This ends up being fairly benign because the side effect is just the invalidation of the authorizer and successive fetching of new tickets. con->v1.connect_seq overlaps with con->v2.conn_bufs and the fact that it's being written to can cause more serious consequences, but luckily it's not something that happens often.

Timeline
Published 2025-09-23
Modified 2026-07-30

External references

Search for exposed instances

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More intel sources (5)

Known PoCs on GitHub

No public proof-of-concept repositories found for CVE-2025-39880 on GitHub.