CVE-2021-26074 json
Broken Authentication in Atlassian Connect Spring Boot
published 2021-04-16 5 y ago modified 2026-06-17 4 mo ago also GHSA-cpcr-74q9-74gp , EUVD-2021-1047
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 52%
- public exploits
- 0
- none known
Summary
Broken Authentication in Atlassian Connect Spring Boot (ACSB) from version 1.1.0 before version 2.1.3: Atlassian Connect Spring Boot is a Java Spring Boot package for building Atlassian Connect apps. Authentication between Atlassian products and the Atlassian Connect Spring Boot app occurs with a server-to-server JWT or a context JWT. Atlassian Connect Spring Boot versions from version 1.1.0 before version 2.1.3 erroneously accept context JWTs in lifecycle endpoints (such as installation) where only server-to-server JWTs should be accepted, permitting an attacker to send authenticated re-installation events to an app.
Patch / fix
- maven com.atlassian.connect:atlassian-connect-spring-boot-starter 2.1.3
- Atlassian Atlassian Connect Spring Boot (ACSB) 2.1.3
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 20 mo ago
Exploit prediction
0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| NVD | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:N/I:P/A:N |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | com.atlassian.connect:atlassian-connect-spring-boot-starter | >=1.1.0, <2.1.3 |
2.1.3 |
Affected products
- Atlassian Atlassian Connect Spring Boot (ACSB)
Classification
- Weakness
- Technology feeds
References
-
confluence.atlassian.com
/pages/viewpage.action?pageId=1051986106
web, vendor-advisory
-
community.developer.atlassian.com
/t/action-required-atlassian-connect-vulnerability-allows-bypass-of-app-qsh-verification-via-context-jwts/4707
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-26074
advisory
Sources
- CVE List CVE-2021-26074
- GitHub Advisory GHSA-cpcr-74q9-74gp
- NVD CVE-2021-26074
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