CVE-2021-21607Network attack vector

Service crash via unbounded graph dimensions

Published Jan 13, 2021 · Updated Aug 3, 2024

Denial of service in Jenkins 2.274 and earlier and LTS 2.263.1 and earlier allows remote authenticated users to crash Jenkins via graph URLs. Graph.render parses attacker-controlled width and height parameters and passes them to createBufferedImage without bounding their pixel area. Low-privilege access can rapidly exhaust the controller heap; alternatively, an attacker can induce a legitimate user to request the crafted URL.

CVSS severity6.5
Medium
EPSS probability1.44%
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 Jenkins 2.274 and earlier and LTS 2.263.1 and earlier allows remote authenticated users to crash Jenkins via graph URLs. Graph.render parses attacker-controlled width and height parameters and passes them to createBufferedImage without bounding their pixel area. Low-privilege access can rapidly exhaust the controller heap; alternatively, an attacker can induce a legitimate user to request the crafted URL.

The record

CVE
CVE-2021-21607
Published
Jan 13, 2021
Updated
Aug 3, 2024
Vendor
Jenkins Project
Product
Jenkins
Classifications
CWE-770, T1499.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=unspecified <=2.274
  2. Affected versionversion=unspecified <=LTS 2.263.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Jenkins Project · Jenkinsversion=unspecified <=2.274; version=unspecified <=LTS 2.263.1

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
6.5GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.0NIST NVDAV:N/AC:L/Au:S/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.003Application Exhaustion Flood

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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