Skip to content
Fencer Vulns
high 7.3

CVE-2026-9334 json

Cpanel::JSON::XS versions before 4.41 for Perl allow type confusion via duplicate object keys when dupkeys_as_arrayref is enabled

published 2026-06-03 5 mo ago modified 2026-07-21 3 mo ago also EUVD-2026-34060

cvss
7.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits
0
none known

Summary

Cpanel::JSON::XS versions before 4.41 for Perl allow type confusion via duplicate object keys when dupkeys_as_arrayref is enabled.

decode_hv() collapses duplicate object keys into an array reference under dupkeys_as_arrayref. The branch reached for a duplicate key tests `SvTYPE (old_value) != SVt_RV && SvTYPE (SvRV (old_value)) != SVt_PVAV`, which evaluates SvRV(old_value) before establishing that old_value is a reference. When the existing value is a plain scalar rather than an array reference, a non-reference scalar is dereferenced as a reference.

A caller decoding untrusted JSON with dupkeys_as_arrayref enabled is crashed, and the incompatible access follows a pointer taken from attacker controlled scalar contents.

Patch / fix

  • RURBAN Cpanel::JSON::XS 4.41
  • libcpanel-json-xs-perl Debian 14 4.41-1

debian advisories DEBIAN-CVE-2026-9334

  • perl-Cpanel-JSON-XS SLE Module for Package Hub 15 SP7 4.800.0-150700.3.9.1
  • perl-Cpanel-JSON-XS SLE Module for Package Hub 15 SP7 4.380.0-150700.3.6.1

suse advisories SUSE-SU-2026:4926-1SUSE-SU-2026:2782-1

  • perl-Cpanel-JSON-XS openSUSE Leap 16.0 4.420.0-bp160.1.1
  • perl-Cpanel-JSON-XS openSUSE Tumbleweed 4.410.0-1.1

opensuse advisories openSUSE-SU-2026:21140-1openSUSE-SU-2026:10950-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-9334 updated cvss 7.5

perl-Cpanel-JSON-XS: perl-Cpanel-JSON-XS: Denial of Service via type confusion with duplicate JSON object keys

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
5 mo ago

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CNA 3.1 7.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Affected products

  • RURBAN Cpanel::JSON::XS

Classification

Weakness
  • CWE-843 Access of Resource Using Incompatible Type

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.