cPanel CVE-2026-110674
CVE-2026-110674 is one of a coordinated set of fixes in Cpanel::JSON::XS for Perl: versions before 4.80 — miss duplicate non-ascii bare keys, allowing type confusion under dupkeys_as_arrayref in decode_hv. The corrected build is Cpanel::JSON::XS 4.80, delivered to cPanel & WHM servers through the standard update channel.
What this means under a SharedLicense license
Parsing untrusted JSON with the affected Cpanel::JSON::XS builds is the exposure: CWE-176 in the advisory's own data, CVSS 6.5 — practical risk ranges from resource exhaustion to memory corruption.
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.
Reference: https://nvd.nist.gov/vuln/detail/CVE-2026-110674
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