CVE-2025-39880

Medium

Elevated severity or exploit probability.

CVSS base

9.8 CRITICAL

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

EPSS — probability of exploitation (30 days)

0.3%

25.6th percentile

CISA KEV

Not listed

Weakness / dates

CWE-704

Published 2025-09-23 · modified 2026-07-30

CVSS breakdown

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

Attack Vector	N	Network
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	H	High
Integrity	H	High
Availability	H	High

Timeline

2025-09-23 — Published (NVD)
2026-07-30 — Last modified (NVD)

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.

Affected

debian linux

References

Official: NVD · CVE.org