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CVE-2021-43776

XSS vulnerability in @backstage/plugin-auth-backend

Published: Nov 26, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-79
NVD MITRE
7.4CVSSHIGH
EPSS Score
0.7%
Top 53.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

Backstage is an open platform for building developer portals. In affected versions the auth-backend plugin allows a malicious actor to trick another user into visiting a vulnerable URL that executes an XSS attack. This attack can potentially allow the attacker to exfiltrate access tokens or other secrets from the user's browser. The default CSP does prevent this attack, but it is expected that some deployments have these policies disabled due to incompatibilities. This is vulnerability is patched in version `0.4.9` of `@backstage/plugin-auth-backend`.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:RS:CC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-79

Affected Products

auth backendlinuxfoundation
Mixed
AI / ML / ml-framework
@backstage/plugin-auth-backendnpmOSS Libraries
backstagebackstage
SaaS
DevTools & CI / source-control
linuxfoundationoss-projectUSAI / MLaka yocto, pytorch, everest
npmpackage-ecosystemOSS Libraries
backstagecommercialDevTools & CI

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Execution
Initial Access
View detailed technique mapping

References

https://github.com/backstage/backstage/security/advisories/GHSA-w7fj-336r-vw49
github.com
https://github.com/backstage/backstage/tree/master/plugins/auth-backend
github.com
https://nvd.nist.gov/vuln/detail/CVE-2021-43776
nvd.nist.gov
and 1 more references View all →

Timeline

Published
Nov 26, 2021
Last Updated
Nov 21, 2024

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