Cpanel::JSON::XS versions from 4.51 before 4.80 for Perl allow quadratic CPU use by revalidating the remaining buffer per value in incr_parse. At the first non-ASCII byte in a string, the decoder validates UTF-8 from there to the end of its input. incr_parse decodes each buffered value with a fresh decoder, so every value revalidates the rest of the buffer, and doubling the input quadruples the work. A peer that sends about a megabyte of ordinary non-ASCII JSON in one read ties up the process for seconds of CPU time.
Fix
Nothing published yet: no patch, vendor advisory or mitigation reference on NVD, no vendor advisory in the News for this CVE, not in CISA's KEV, no fixed package version. BaselineWatch does not guess at one.
Change history 3
- StatusAwaiting Analysis → PublishedNVD modified 2026-10-19 18:12
- StatusReceived → Awaiting AnalysisNVD modified 2026-10-19 20:50
- First seenunscoredNVD modified 2026-10-19 19:17
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.