7.5

CVE-2026-68155: linux Improper Input Validation

CVSS: 7.5v3.1HighReceived
AliasesUBUNTU-CVE-2026-68155DEBIAN-CVE-2026-68155
Published 10-08-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-68155 is a high (CVSS 7.5) Improper Input Validation vulnerability in linux. EPSS estimates a 0.70% chance of exploitation in the next 30 days, higher than 52.1% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.70%
0%100%
Low · +0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 38 · Related 32
MGASA-2026-0336MGASA-2026-0337OPENSUSE-SU-2026:21910-1RHSA-2026:70459RHSA-2026:70498RHSA-2026:72467

Timeline

  1. 10-08-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: libceph: Reject monmaps advertising zero monitors A message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a monitor to the client. This monmap contains information about the existing monitors in the cluster. Currently, a monmap indicating that there are zero monitors in the cluster is treated as valid. However, it is impossible to have zero monitors in the cluster and still receive a valid monmap from a monitor. Therefore, such a monmap must be corrupted and should be treated as invalid. Furthermore, a monmap with a monitor count of zero can subsequently crash the client when attempting to open a session with a monitor in __open_session(). This happens because the "BUG_ON(monc->monmap->num_mon < 1)" assertion in pick_new_mon() is triggered. This patch extends a check in ceph_monmap_decode() to also reject arriving mon_maps with num_mon == 0 rather than only with num_mon > CEPH_MAX_MON. [ idryomov: drop "log output for unusual values of num_mon" part ]

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.70%

Chance of exploitation in the next 30 days

Percentile

52%

Versus all other CVEs

30-day change

+0.03 pp

From 0.66% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.70%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu169 products
  • linuxAll versions (No fix recorded) | < 5.15.0-198.208 | < 6.8.0-147.147 | < 7.0.0-38.38
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124 | < 6.8.0-1067.70 | < 7.0.0-1014.14
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.187-1 | < 6.12.101-1 | < 7.1.6-1
  • linux-6.12< 6.12.101-1~deb12u1
Linux1 product
  • linux≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < ba5f0015bfd376d764163045a61c17be75f44dae | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < caf082ef8609a6ac26159ce115f55ab7d00231a3 | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < e3ccd4ecab09b22f507f49cb7ed9990c7158ceab | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < 0591a15815b498be628a937146e44487d599ba33 | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < cd0d41bc569632eaaeccde9d2a6bc919ec00c407 | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < e67e8b694872c9bc66996040f9de9242f6236ed9 | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < 3b249546f59c3d6d3592c10657f82bc3f1faa07c | ≥ ba75bb98cfb93b62c54af25bf67ff90857264bbe, < 40480eee361ed9676b3f844d532ac28b47251634 | 2.6.34

3 vendors · 172 products

References

26 links
Show all 26 references