cPanel CVE-2026-110686
CVE-2026-110686 is one of a coordinated set of fixes in Cpanel::JSON::XS for Perl: versions before 4.80 — use freed filter callbacks when a filter removes itself during decoding 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-416 in the advisory's own data, CVSS 6.5 — practical risk ranges from resource exhaustion to memory corruption.
Cpanel::JSON::XS versions before 4.80 for Perl use freed filter callbacks when a filter removes itself during decoding in decode_hv.
A decode copies the parser’s filter_json_object and filter_json_single_key_object callbacks without taking references to them. A filter callback that removes the last single-key filter frees the callback table while the decode in progress still uses it. The next object is dispatched through freed memory and can crash the process.
Reference: https://nvd.nist.gov/vuln/detail/CVE-2026-110686
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