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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
7.4HIGH
NVD MITRE
EPSS Score
0.7%
Top 51.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
Not 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`.

No summary for this CVE yet.

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

linuxfoundation
oss-project·USaka yocto, everest, pytorch
auth backend
AI / ML
npm
package-ecosystem
@backstage/plugin-auth-backend
OSS Libraries
backstage
commercial
backstageSaaS
DevTools & CI / source-control

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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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 →

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