cPanel CVE-2026-110678
CVE-2026-110678 is one of a coordinated set of fixes in Cpanel::JSON::XS for Perl: versions before 4.80 — allow memory exhaustion by buffering incremental input past max_size in incr_parse. 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-770 in the advisory's own data, CVSS 7.5 — practical risk ranges from resource exhaustion to memory corruption.
Cpanel::JSON::XS versions before 4.80 for Perl allow memory exhaustion by buffering incremental input past max_size in incr_parse.
The parser appends each chunk to its buffer. In scalar or list context, it compares max_size with how far it has progressed, not with the buffer length. A chunk that starts with a NUL byte stops the parser before it progresses, and a call in void context skips the check, so the buffer grows without limit.
A peer streaming data to an incr_parse consumer can exhaust process memory regardless of max_size.
Reference: https://nvd.nist.gov/vuln/detail/CVE-2026-110678
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