Vulnerability in Rurban Cpanel\
CVE-2026-9334
Cpanel::JSON::XS versions before 4.41 for Perl allow type confusion via duplicate object keys when dupkeys_as_arrayref is enabled. decode_hv() collapses duplicate object keys into an array reference under dupkeys_as_arrayref. The branch reached for a duplicate key tests `SvTYPE (old_value) != SVt_RV && SvTYPE (SvRV (old_value)) != SVt_PVAV`, which evaluates SvRV(old_value) before establishing that old_value is a reference. When the existing value is a plain scalar rather than an array reference, a non-reference scalar is dereferenced as a reference. A caller decoding untrusted JSON with dupkeys_as_arrayref enabled is crashed, and the incompatible access follows a pointer taken from attacker controlled scalar contents.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.004 (33.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.002
Affected products
- Rurban Cpanel\ — versions \
- Rurban Cpanel::json::xs — versions 0
- Rurban Cpanel\:\:json\:\:xs
Weakness classification (CWE)
References
- 9b29abf9-4ab0-4765-b253-1875cd9b441e (Patch, patch)
- 9b29abf9-4ab0-4765-b253-1875cd9b441e (release-notes, Release Notes)
- af854a3a-2127-422b-91ae-364da2661108 (Patch, Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-9334?
- CVE-2026-9334 is a high-severity vulnerability in Rurban Cpanel\, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 7.3/10. Published 2026-06-03.
- How severe is CVE-2026-9334?
- High severity. CVSS v3 base score is 7.3 out of 10.