CVE-2021-26068Network attack vector

Authenticated code execution via template injection

Published Feb 18, 2021 · Updated Sep 16, 2024

Template injection in Atlassian Jira Server for Slack 0.0.3 through 2.0.14 allows remote authenticated users to execute arbitrary code. The affected plugin endpoint evaluates attacker-supplied template content instead of treating it as data, but Atlassian has not disclosed the endpoint, template engine, or code locus. Exploitation requires any authenticated Jira account and the non-default plugin on Jira Server or Data Center; Jira Cloud is unaffected.

CVSS severity8.8
High
EPSS probability3.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Template injection in Atlassian Jira Server for Slack 0.0.3 through 2.0.14 allows remote authenticated users to execute arbitrary code. The affected plugin endpoint evaluates attacker-supplied template content instead of treating it as data, but Atlassian has not disclosed the endpoint, template engine, or code locus. Exploitation requires any authenticated Jira account and the non-default plugin on Jira Server or Data Center; Jira Cloud is unaffected.

The record

CVE
CVE-2021-26068
Published
Feb 18, 2021
Updated
Sep 16, 2024
Vendor
Atlassian
Product
Jira Server for Slack
Classifications
CWE-74, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=0.0.3 <unspecified
  2. Affected versionversion=unspecified <2.0.15

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Atlassian · Jira Server for Slackversion=0.0.3 <unspecified; version=unspecified <2.0.15

Published CVSS scores

9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
T1190Exploit Public-Facing Application

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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