Heap overflow in libnv

published 2026-04-30 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-26355

cvss: 8.1; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

When processing the header of an incoming message, libnv failed to properly validate the message size.

The lack of validation allows a malicious program to write outside the bounds of a heap allocation. This can trigger a crash or system panic, and it may be possible for an unprivileged user to exploit the bug to elevate their privileges.

Patch / fix

fixed in 1

FreeBSD FreeBSD p3, p7, p12, p13

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 6 mo ago (2026-05-01)

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	3.1	8.1	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

FreeBSD FreeBSD

Classification

Weakness

CWE-122 Heap-based Buffer Overflow
CWE-130 Improper Handling of Length Parameter Inconsistency

References

security.freebsd.org /advisories/FreeBSD-SA-26:17.libnv.asc
vendor-advisory

Sources

CVE List CVE-2026-35547
NVD CVE-2026-35547

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary