CVE-2026-110684

Publication date 19 October 2026

Last updated 13 November 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Cpanel::JSON::XS versions from 3.0202 before 4.80 for Perl leak memory and retain overloaded objects when encoding values as strings in encode_stringify. encode_stringify writes a value in its string form under allow_stringify, under convert_blessed for objects without TO_JSON, and under allow_bignum. For an array or hash object with a "" overload, and from 4.20 a scalar object, it takes an extra reference that is never released, so the object and everything it references are never freed. From 4.10 it also never frees its copy of the string. Repeatedly encoding data that contains such values grows process memory without bound.

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	Vulnerable
	18.04 LTS bionic	Vulnerable
	16.04 LTS xenial	Vulnerable

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: 5b15916

Severity score breakdown

CVSS version: CVSS v3.0

Base score 8.1 · High

Base metrics

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

Scores

Parameter	Value
Base score	8.1 · High
Exploitability score	-
Impact score	-

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