CVE-2024-13926Public exploitNetwork attack vector

Authenticated service interruption via catastrophic regex backtracking

Published Apr 19, 2025 · Updated Aug 27, 2025

Regular-expression denial of service in Connections Pro WP-Syntax 1.2 and earlier allows remote authenticated users to interrupt service. The beforeFilter method passes the full post body to preg_replace_callback with repeated pre-tag attribute alternatives and an unbounded body capture, causing catastrophic backtracking on many unmatched opening tags. An Author-level account must first publish the crafted post; concurrent requests to that page then consume a CPU core per request for several seconds.

CVSS severity7.5
High
EPSS probability0.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Regular-expression denial of service in Connections Pro WP-Syntax 1.2 and earlier allows remote authenticated users to interrupt service. The beforeFilter method passes the full post body to preg_replace_callback with repeated pre-tag attribute alternatives and an unbounded body capture, causing catastrophic backtracking on many unmatched opening tags. An Author-level account must first publish the crafted post; concurrent requests to that page then consume a CPU core per request for several seconds.

The record

CVE
CVE-2024-13926
Published
Apr 19, 2025
Updated
Aug 27, 2025
Vendor
Connections Pro
Product
WP-Syntax
Classifications
CWE-1333, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 19, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2025Record 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 <=1.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Connections Pro · WP-Syntaxversion=0 <=1.2

Published CVSS scores

4.3Wordfence IntelligenceCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitPublished

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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