CVE-2026-110675

Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl accept malformed UTF-8 in bare hash keys under allow_barekey in decode_hv

Published Oct 19, 2026 CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed
Description
Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl accept malformed UTF-8 in bare hash keys under allow_barekey in decode_hv.

With utf8 and allow_barekey, which relaxed enables, a quoted key is validated as UTF-8 but a bare key's bytes are stored as a UTF-8 flagged string without any check. Malformed UTF-8, control bytes and backslashes reach the decoded hash, while malformed UTF-8 and control bytes in a quoted key or a value are rejected.

Later operations on the key, including lc, uc or encoding the hash again, die with a malformed UTF-8 error.

Remediation

Vendor Solution

Upgrade to Cpanel-JSON-XS 4.80 or later.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H'}

Type Values Removed Values Added
First Time appeared Rurban
Rurban cpanel::json::xs
Vendors & Products Rurban
Rurban cpanel::json::xs
Type Values Removed Values Added
Description Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl accept malformed UTF-8 in bare hash keys under allow_barekey in decode_hv. With utf8 and allow_barekey, which relaxed enables, a quoted key is validated as UTF-8 but a bare key's bytes are stored as a UTF-8 flagged string without any check. Malformed UTF-8, control bytes and backslashes reach the decoded hash, while malformed UTF-8 and control bytes in a quoted key or a value are rejected. Later operations on the key, including lc, uc or encoding the hash again, die with a malformed UTF-8 error.
Title Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl accept malformed UTF-8 in bare hash keys under allow_barekey in decode_hv
Weaknesses CWE-1286
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
CPANSec
Published
Updated
Oct 29, 2026, 4:38 PM
Reserved
Oct 14, 2026, 1:23 PM
Status
Awaiting Analysis
Published
Oct 19, 2026, 7:17 PM
Modified
Oct 29, 2026, 5:17 PM