CVE-2026-14803Network attack vector

Memory exhaustion via unbounded JSON nesting

Published Jul 6, 2026 · Updated Jul 6, 2026

Uncontrolled recursion in Mojo::JSON before 9.47 allows remote authenticated users to exhaust process memory with deeply nested JSON. The pure-Perl _decode_value path recursively dispatches to _decode_array and _decode_object without limiting nesting depth. Exposure requires untrusted JSON to reach that decoder, which is used when Cpanel::JSON::XS is unavailable or MOJO_NO_JSON_XS is set, and memory exhaustion interrupts the hosting process.

CVSS severity6.5
Medium
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled recursion in Mojo::JSON before 9.47 allows remote authenticated users to exhaust process memory with deeply nested JSON. The pure-Perl _decode_value path recursively dispatches to _decode_array and _decode_object without limiting nesting depth. Exposure requires untrusted JSON to reach that decoder, which is used when Cpanel::JSON::XS is unavailable or MOJO_NO_JSON_XS is set, and memory exhaustion interrupts the hosting process.

The record

CVE
CVE-2026-14803
Published
Jul 6, 2026
Updated
Jul 6, 2026
Vendor
Mojolicious
Product
Mojo::JSON
Classifications
CWE-674, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <9.47

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mojolicious · Mojo::JSONversion=0 <9.47

Published CVSS scores

6.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-674Uncontrolled Recursion
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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