CVE-2026-75140Network attack vector

JVM heap exhaustion via namespace map copying

Published Aug 20, 2026 · Updated Aug 20, 2026

Uncontrolled resource consumption in Jonathan Hedley jsoup 1.23.1 and earlier allows remote attackers to crash XML-parsing applications. In XmlTreeBuilder, each start element clones the full inherited namespace map before applying new declarations, so deeply nested uniquely namespaced elements drive quadratic memory and time growth. Reachability depends on parsing attacker-controlled XML with jsoup's XML parser; successful exploitation exhausts JVM heap and terminates the process with an OutOfMemoryError.

CVSS severity8.7
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in Jonathan Hedley jsoup 1.23.1 and earlier allows remote attackers to crash XML-parsing applications. In XmlTreeBuilder, each start element clones the full inherited namespace map before applying new declarations, so deeply nested uniquely namespaced elements drive quadratic memory and time growth. Reachability depends on parsing attacker-controlled XML with jsoup's XML parser; successful exploitation exhausts JVM heap and terminates the process with an OutOfMemoryError.

The record

CVE
CVE-2026-75140
Published
Aug 20, 2026
Updated
Aug 20, 2026
Vendor
Jonathan Hedley
Product
jsoup
Classifications
CWE-770, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 20, 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 <=1.23.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Jonathan Hedley · jsoupversion=0 <=1.23.1

Published CVSS scores

7.5VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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