CVE-2023-33546Public exploit

Application crash via unbounded expression recursion

Published Jun 1, 2023 · Updated Aug 2, 2024

Denial of service in Janino 3.1.9 and earlier allows attackers to crash a host application by submitting a deeply nested expression. ExpressionEvaluator.guessParameterNames recursively parses nested parentheses without containing StackOverflowError, allowing parser recursion to exhaust the JVM thread stack. The host application must pass attacker-controlled source text to the API; the CVE is disputed because multiple parties contend that Janino is not intended for untrusted input.

CVSS severity5.5
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Janino 3.1.9 and earlier allows attackers to crash a host application by submitting a deeply nested expression. ExpressionEvaluator.guessParameterNames recursively parses nested parentheses without containing StackOverflowError, allowing parser recursion to exhaust the JVM thread stack. The host application must pass attacker-controlled source text to the API; the CVE is disputed because multiple parties contend that Janino is not intended for untrusted input.

The record

CVE
CVE-2023-33546
Published
Jun 1, 2023
Updated
Aug 2, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 1, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/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.

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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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
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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