CVE-2023-34624Public exploitNetwork attack vector

Application crash via unbounded recursive tag traversal

Published Jun 14, 2023 · Updated Jan 6, 2025

Stack exhaustion in the HtmlCleaner parser before 2.29 allows remote attackers to crash applications with excessively nested HTML. HtmlCleaner.markNodesToPrune recursively traverses the unbounded tag tree, exhausting the Java call stack before parsing completes. An application must pass attacker-controlled HTML to the library; the demonstrated consequence is a StackOverflowError and process-level service interruption.

CVSS severity7.5
High
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack exhaustion in the HtmlCleaner parser before 2.29 allows remote attackers to crash applications with excessively nested HTML. HtmlCleaner.markNodesToPrune recursively traverses the unbounded tag tree, exhausting the Java call stack before parsing completes. An application must pass attacker-controlled HTML to the library; the demonstrated consequence is a StackOverflowError and process-level service interruption.

The record

CVE
CVE-2023-34624
Published
Jun 14, 2023
Updated
Jan 6, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-400, CWE-787, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 6, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.

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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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
CWE-787Out-of-bounds Write
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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