Vulnerability · Published Jul 6, 2026 · Assigned by CPANSec
CVE-2026-14803Mojo::JSON versions before 9.47 for Perl allow memory exhaustion via unbounded recursion in the pure-Perl decoder
Medium 6.5
In plain English
A medium-severity security flaw in Mojo::JSON from SRI. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Mojo::JSON versions before 9.47 for Perl allow memory exhaustion via unbounded recursion in the pure-Perl decoder. The pure-Perl decode path (`_decode_value` dispatching to `_decode_array` and `_decode_object`) recurses with no depth limit, so a small deeply nested JSON document can consume excessive memory. This path is the default when Cpanel::JSON::XS is not installed or `MOJO_NO_JSON_XS=1` is set; the Cpanel::JSON::XS fast path is not affected. Any caller that decodes an untrusted JSON body, for example `Mojo::Message::json` reached through `$c->req->json`, can exhaust process memory and cause denial of service.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libmojolicious-perl | no fix listed | DEBIAN-CVE-2026-14803 |
| Debian:13 | libmojolicious-perl | no fix listed | DEBIAN-CVE-2026-14803 |
| Debian:14 | libmojolicious-perl | 9.47+dfsg-1 | DEBIAN-CVE-2026-14803 |
| Ubuntu:22.04:LTS | libmojolicious-perl | no fix listed | UBUNTU-CVE-2026-14803 |
| Ubuntu:24.04:LTS | libmojolicious-perl | no fix listed | UBUNTU-CVE-2026-14803 |
| Ubuntu:25.10 | libmojolicious-perl | no fix listed | UBUNTU-CVE-2026-14803 |
| Ubuntu:26.04:LTS | libmojolicious-perl | no fix listed | UBUNTU-CVE-2026-14803 |
| Ubuntu:26.10 | libmojolicious-perl | no fix listed | UBUNTU-CVE-2026-14803 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| SRI | Mojo::JSON | 0 – before 9.47 |
Weakness: CWE-674 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H