CVE-2026-16270Network attack vector

Service interruption via unsafe custom-field regex

Published Jul 22, 2026 · Updated Jul 22, 2026

Regular expression denial of service in Open Mercato before 0.6.4 allows remote authenticated users to interrupt service. The custom-field validator applies administrator-supplied patterns to field values with native JavaScript regular expressions and no complexity or size bounds. High privileges are required to create the rule; a later matching value can trigger catastrophic backtracking and exhaust processing time.

CVSS severity6.9
Medium
EPSS probability0.48%
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 Open Mercato before 0.6.4 allows remote authenticated users to interrupt service. The custom-field validator applies administrator-supplied patterns to field values with native JavaScript regular expressions and no complexity or size bounds. High privileges are required to create the rule; a later matching value can trigger catastrophic backtracking and exhaust processing time.

The record

CVE
CVE-2026-16270
Published
Jul 22, 2026
Updated
Jul 22, 2026
Vendor
Open Mercato
Product
Open Mercato
Classifications
CWE-1333, T1499.004
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jul 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 22, 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 <0.6.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Open Mercato · Open Mercatoversion=0 <0.6.4

Published CVSS scores

6.9CERT.PLCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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

Public exploit references

No public exploit references are available in this record.

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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