CVE-2025-3986Public exploitNetwork attack vector

Service interruption via crafted Name regular expression

Published Apr 27, 2025 · Updated Apr 28, 2025

Inefficient regular expression complexity in Apereo CAS 5.2.6 allows remote authenticated users to interrupt service via a crafted Name value. CasConfigurationMetadataServerController evaluates the attacker-controlled Name argument as a regular expression without constraining its computational complexity. Low-privileged network access to the endpoint is required, and pathological matching consumes processing resources until availability degrades.

CVSS severity7.5
High
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Inefficient regular expression complexity in Apereo CAS 5.2.6 allows remote authenticated users to interrupt service via a crafted Name value. CasConfigurationMetadataServerController evaluates the attacker-controlled Name argument as a regular expression without constraining its computational complexity. Low-privileged network access to the endpoint is required, and pathological matching consumes processing resources until availability degrades.

The record

CVE
CVE-2025-3986
Published
Apr 27, 2025
Updated
Apr 28, 2025
Vendor
Apereo
Product
Apereo CAS
Classifications
CWE-400, CWE-1333, T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 27, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 28, 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=5.2.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Apereo · Apereo CASversion=5.2.6

Published CVSS scores

5.3VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
4.0VulDB CNAAV:N/AC:L/Au:S/C:N/I:N/A:P
4.3VulDB CNACVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
4.3VulDB CNACVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
CWE-1333Inefficient Regular Expression Complexity
T1499Endpoint Denial of Service

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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