CVE-2021-36374

Build crash via unchecked ZIP link length

Published Jul 14, 2021 · Updated Aug 4, 2024

Resource exhaustion in Apache Ant 1.4 through 1.9.15 and 1.10.0 through 1.10.10 allows local users to crash builds via crafted ZIP archives. AsiExtraField.parseFromLocalFileData trusts a four-byte symbolic-link length in an ASi Unix extra field and allocates that many bytes before checking it against the remaining field data. Exploitation requires a build to read or update an attacker-supplied ZIP-derived archive and interrupts that Ant process when memory is exhausted.

CVSS severity5.5
Medium
EPSS probability2.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in Apache Ant 1.4 through 1.9.15 and 1.10.0 through 1.10.10 allows local users to crash builds via crafted ZIP archives. AsiExtraField.parseFromLocalFileData trusts a four-byte symbolic-link length in an ASi Unix extra field and allocates that many bytes before checking it against the remaining field data. Exploitation requires a build to read or update an attacker-supplied ZIP-derived archive and interrupts that Ant process when memory is exhausted.

The record

CVE
CVE-2021-36374
Published
Jul 14, 2021
Updated
Aug 4, 2024
Vendor
The Apache Software Foundation
Product
Apache Ant
Classifications
CWE-130, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 14, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.4 <Apache Ant*
  2. Affected versionversion=Apache Ant 1.10.x <=1.10.10
  3. Affected versionversion=Apache Ant 1.9.x <=1.9.15

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Antversion=1.4 <Apache Ant*; version=Apache Ant 1.10.x <=1.10.10; version=Apache Ant 1.9.x <=1.9.15

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P

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 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 exploitUnconfirmed

Weakness, pattern, technique

CWE-130Improper Handling of Length Parameter Inconsistency
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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