CVE-2026-14803 | Mojo::JSON versions before 9.47 for Perl allow memory exhaustion via unbounded recursion in the pure-Perl decoder

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.

Published: 2026-07-05 Last update: 2026-07-06 Assigner: 9b29abf9-4ab0-4765-b253-1875cd9b441e Source: 9b29abf9-4ab0-4765-b253-1875cd9b441e
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-14803 is rated Low Risk (34.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.33%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-14803

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-07-07 0.19% 0.33% +0.14%
2 2026-07-06 — 0.19% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-14803

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-14803

GitHub Security Advisory for CVE-2026-14803

GHSA-fp7f-j7qv-4qww · Severity: medium — Mojo::JSON versions before 9.47 for Perl allow memory exhaustion via unbounded recursion in the...

OS Trackers for CVE-2026-14803

vendor priority summary link
debian not yet assigned CVE-2026-14803 not yet assigned priority: Debian including 1 source packages (libmojolicious-perl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-14803
ubuntu medium CVE-2026-14803 medium priority: Ubuntu including 1 source packages (libmojolicious-perl), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): needs-triage 6, ignored 1. https://ubuntu.com/security/CVE-2026-14803

Affected software / configurations for CVE-2026-14803

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-14803

cvelogic Threat Intelligence