CVE-2026-9516 Affecting libcpanel-json-xs-perl package, versions <4.41-1


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.62% (48th percentile)

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  • Snyk IDSNYK-DEBIAN14-LIBCPANELJSONXSPERL-17099895
  • published30 May 2026
  • disclosed3 Jun 2026

Introduced: 30 May 2026

CVE-2026-9516  (opens in a new tab)

How to fix?

Upgrade Debian:14 libcpanel-json-xs-perl to version 4.41-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libcpanel-json-xs-perl package and not the libcpanel-json-xs-perl package as distributed by Debian. See How to fix? for Debian:14 relevant fixed versions and status.

Cpanel::JSON::XS versions before 4.41 for Perl allow denial of service via UTF-8 BOM prefixed input when a decode filter callback throws.

To skip a leading 3-byte UTF-8 BOM, decode_json() advances the input scalar's string pointer past the mark with SvPV_set() and restores it only on the normal return path. When decoding aborts through a Perl exception, for example a filter_json_object callback that croaks, the restore is skipped and the scalar is left with its string pointer offset into its own buffer and a shortened length.

When that scalar is later freed, the allocator receives an invalid pointer and the interpreter aborts. A single BOM prefixed document decoded with a throwing filter callback crashes any caller.

CVSS Base Scores

version 3.1