Cpanel::JSON::XS versions from 4.33 before 4.80 for Perl miss duplicate non-ASCII bare keys, allowing type confusion under dupkeys_as_arrayref in decode_hv.
With allow_barekey, which relaxed enables, a bare key containing a non-ASCII byte is stored as UTF-8 but looked up as raw bytes, so a repeated key escapes the duplicate-key check and replaces the earlier value.
From 4.41, under dupkeys_as_arrayref, a bare repeat replaces the array that collects a key's values with a plain value, and the next quoted repeat pushes onto that value as if it were an array. A JSON integer there is dereferenced as a pointer.
Untrusted JSON decoded with relaxed and dupkeys_as_arrayref can crash the process or dereference an address chosen by a JSON number.
References
Configurations
No configuration.
History
29 Oct 2026, 17:17
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 6.5 |
19 Oct 2026, 19:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-10-19 19:17
Updated : 2026-10-29 17:17
NVD link : CVE-2026-110674
Mitre link : CVE-2026-110674
CVE.ORG link : CVE-2026-110674
JSON object : View
Products Affected
No product.