cPanel CVE-2026-110680
CVE-2026-110680 is one of a coordinated set of fixes in Cpanel::JSON::XS for Perl: versions before 4.80 — write out of bounds when a tied or shared hash grows during canonical encoding in encode_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-787 in the advisory's own data, CVSS 7.5 — practical risk ranges from resource exhaustion to memory corruption.
Cpanel::JSON::XS versions from 4.20 before 4.80 for Perl write out of bounds when a tied or shared hash grows during canonical encoding in encode_hv.
With canonical, the keys of a tied or threads::shared hash are counted before a second pass collects them for sorting. The encoder uses a fixed 64-entry stack array or, for larger counts, a heap array sized from the first pass. If the second pass exceeds that capacity, entries are written out of bounds before the counts are compared.
This corrupts stack or heap memory and can crash the process.
Reference: https://nvd.nist.gov/vuln/detail/CVE-2026-110680
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