CVE-2021-39116Network attack vector

Service interruption via crafted GIF processing

Published Sep 8, 2021 · Updated Oct 10, 2024

DoS in Atlassian Jira Server and Data Center before 8.13.14 and from 8.14.0 before 8.19.0 allows remote attackers to interrupt service. The GIF Image Reader processes the crafted image, but Atlassian has not disclosed the parser operation or resource condition that causes availability loss. Processing the file is required; the delivery path, authentication gate, and whether the result is a hang or crash remain undisclosed.

CVSS severity5.5
Medium
EPSS probability1.07%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

DoS in Atlassian Jira Server and Data Center before 8.13.14 and from 8.14.0 before 8.19.0 allows remote attackers to interrupt service. The GIF Image Reader processes the crafted image, but Atlassian has not disclosed the parser operation or resource condition that causes availability loss. Processing the file is required; the delivery path, authentication gate, and whether the result is a hang or crash remain undisclosed.

The record

CVE
CVE-2021-39116
Published
Sep 8, 2021
Updated
Oct 10, 2024
Vendor
Atlassian
Product
Jira Server
Classifications
T1499
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 10, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=8.14.0 <unspecified
  2. Affected versionversion=unspecified <8.13.14
  3. Affected versionversion=unspecified <8.19.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

Atlassian · Jira Serverversion=8.14.0 <unspecified; version=unspecified <8.13.14; version=unspecified <8.19.0
Atlassian · Jira Data Centerversion=8.14.0 <unspecified; version=unspecified <8.13.14; version=unspecified <8.19.0

Published CVSS scores

4.3NISTAV:N/AC:M/Au:N/C:N/I:N/A:P
5.5NISTCVSS: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.

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)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo