CVE-2026-110680

Publication date 19 October 2026

Last updated 13 November 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Cpanel::JSON::XS versions from 4.20 before 4.80 for Perl write out of bounds when a tied or shared hash grows during canonical encoding in encode_hv. With canonical, the keys of a tied or threads::shared hash are counted before a second pass collects them for sorting. The encoder uses a fixed 64-entry stack array or, for larger counts, a heap array sized from the first pass. If the second pass exceeds that capacity, entries are written out of bounds before the counts are compared. This corrupts stack or heap memory and can crash the process.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libcpanel-json-xs-perl	26.10 stonking	Vulnerable
	26.04 LTS resolute	Vulnerable
	24.04 LTS noble	Vulnerable
	22.04 LTS jammy	Vulnerable
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected

Patch details

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

Package	Patch details
libcpanel-json-xs-perl	Upstream: 44c4591

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · High

Base metrics

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

Scores

Parameter	Value
Base score	7.5 · High
Exploitability score	-
Impact score	-

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