CVE-2026-110674 Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl miss duplicate non-ASCII bare keys, allowing type confusion under dupkeys_as_arrayref in decode_hv.
- Exploited in the wild
- Not known
- Fix
- Available
What is CVE-2026-110674?
CVE-2026-110674 is a medium-severity vulnerability, published on 19 Oct 2026.
Official description
Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl miss duplicate non-ASCII bare keys, allowing type confusion under dupkeys_as_arrayref in decode_hv.
With allow_barekey, which relaxed enables, a bare key containing a non-ASCII byte is stored as UTF-8 but looked up as raw bytes, so a repeated key escapes the duplicate-key check and replaces the earlier value.
From 4.41, under dupkeys_as_arrayref, a bare repeat replaces the array that collects a key's values with a plain value, and the next quoted repeat pushes onto that value as if it were an array. A JSON integer there is dereferenced as a pointer.
Untrusted JSON decoded with relaxed and dupkeys_as_arrayref can crash the process or dereference an address chosen by a JSON number.
Which versions are affected by CVE-2026-110674?
How do I fix CVE-2026-110674?
Upgrade to a fixed version.
Is CVE-2026-110674 being exploited?
There is no known exploitation of CVE-2026-110674 in the wild and no public exploit code.
Sources
Also known as AZL-109836, DEBIAN-CVE-2026-110674, GHSA-c92x-ph36-v6p2, UBUNTU-CVE-2026-110674.