CVE-2026-53689

Publication date 11 June 2026

Last updated 25 June 2026

Ubuntu priority

Cvss 3 Severity Score

Description

libnfs through 6.0.2 before 55c18ea does not validate a string size, leading to an integer overflow during a connection to a crafted NFS server. This occurs in libnfs_zdr_string in lib/libnfs-zdr.c.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libnfs	26.04 LTS resolute	Fixed 5.0.2-1ubuntu1.1
	25.10 questing	Fixed 5.0.2-1ubuntu0.25.10.1
	24.04 LTS noble	Fixed 5.0.2-1ubuntu0.24.04.1
	22.04 LTS jammy	Fixed 4.0.0-1ubuntu0.1
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
libnfs	Upstream: 55c18ea

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.1 · High

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	Low

Scores

Parameter	Value
Base score	7.1 · High
Exploitability score	-
Impact score	-

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

References

Related Ubuntu Security Notices (USN)

USN-8464-1
LIBNFS vulnerability
23 June 2026

Other references

https://www.cve.org/CVERecord?id=CVE-2026-53689