CVE catalog

CVE-2026-9516

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 th

[CVE catalog]

Severity: High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: Jun 3, 2026, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 0.36% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	libcpanel-json-xs-perl	sid	`4.80-1`	fixed
Debian	libcpanel-json-xs-perl	forky	`4.80-1`	fixed
Debian	libcpanel-json-xs-perl	trixie	`4.39-2~deb13u1`	vulnerable
Debian	libcpanel-json-xs-perl	trixie-security	`4.39-2~deb13u1`	vulnerable
Debian	libcpanel-json-xs-perl	bookworm	`4.35-1+deb12u1`	vulnerable
Debian	libcpanel-json-xs-perl	bookworm-security	`4.35-1+deb12u1`	vulnerable
Cpe	libcpanel-json-xs-perl	Not reported	Not reported	vulnerable
Cpe	cpanel\	Not reported	`4.41`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	libcpanel-json-xs-perl	source	sid	`4.41-1`	not yet assigned	Not reported	[1138273]
Debian	libcpanel-json-xs-perl	source	forky	`4.41-1`	not yet assigned	Not reported	[1138273]
Debian	libcpanel-json-xs-perl	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1138273]
Debian	libcpanel-json-xs-perl	source	bookworm	`(unfixed)`	not yet assigned	Not reported	[1138273]
Cpe	cpanel\	cpe	Not reported	`4.41`	Not reported	Not reported	Not reported

[Debian bug #1138273]

Notes

[trixie] libcpanel-json-xs-perl: Minor issue [bookworm] libcpanel-json-xs-perl: Minor issue

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libcpanel-json-xs-perl]Affected
Details (4)
- 4.35-1+deb12u1 · amd64 · bookworm
  Affected
  nvd · libcpanel-json-xs-perl · debian · bookworm; nvd · libcpanel-json-xs-perl · debian · 12
- 4.35-1+deb12u1 · arm64 · bookworm
  Affected
  nvd · libcpanel-json-xs-perl · debian · bookworm; nvd · libcpanel-json-xs-perl · debian · 12
- 4.35-1+deb12u1 · amd64 · bookworm-security
  Affected
  nvd · libcpanel-json-xs-perl · debian · bookworm; nvd · libcpanel-json-xs-perl · debian · 12
- 4.35-1+deb12u1 · arm64 · bookworm-security
  Affected
  nvd · libcpanel-json-xs-perl · debian · bookworm; nvd · libcpanel-json-xs-perl · debian · 12

[Debian 13 (Trixie)]

[libcpanel-json-xs-perl]Affected
Details (4)
- 4.39-2~deb13u1 · amd64 · trixie
  Affected
  nvd · libcpanel-json-xs-perl · debian · 13
- 4.39-2~deb13u1 · arm64 · trixie
  Affected
  nvd · libcpanel-json-xs-perl · debian · 13
- 4.39-2~deb13u1 · amd64 · trixie-security
  Affected
  nvd · libcpanel-json-xs-perl · debian · 13
- 4.39-2~deb13u1 · arm64 · trixie-security
  Affected
  nvd · libcpanel-json-xs-perl · debian · 13

Observed: Oct 27, 2026, 7:18:45 AM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]