CVE-2026-40319

Process hang via unbounded regular expression matching

Published Apr 17, 2026 · Updated Apr 17, 2026

Regular expression denial of service in Giskard Open Source before 1.0.2b1 allows local users to hang the test process. RegexMatching passes its pattern argument to Python's re.search() without a timeout, complexity limit, or validation, enabling catastrophic backtracking. Exploitation requires write access to a check definition and later execution of the affected test suite; the resulting CPU exhaustion interrupts that process.

CVSS severity1.0
Low
EPSS probability0.15%
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 Giskard Open Source before 1.0.2b1 allows local users to hang the test process. RegexMatching passes its pattern argument to Python's re.search() without a timeout, complexity limit, or validation, enabling catastrophic backtracking. Exploitation requires write access to a check definition and later execution of the affected test suite; the resulting CPU exhaustion interrupts that process.

The record

CVE
CVE-2026-40319
Published
Apr 17, 2026
Updated
Apr 17, 2026
Vendor
Giskard
Product
Giskard Open Source
Classifications
CWE-1333, CAPEC-492, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 17, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 17, 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=< 1.0.2b1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Giskard · Giskard Open Sourceversion=< 1.0.2b1

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
1.0GitHub, Inc.CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA: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.

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

No observations available

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

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
CAPEC-492Regular Expression Exponential Blowup
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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