CVE-2021-37859
Reflected XSS in OAuth Flow
MEDIUM
6.1
CVSS Score
Published: August 5, 2021 at 07:40 PM UTC
Updated: June 17, 2026 at 04:01 AM UTC
1 product affected across 1 vendorMattermost
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Severity
MEDIUM6.1
Exploit prediction
EPSS 3%
Description
Fixed a bypass for a reflected cross-site scripting vulnerability affecting OAuth-enabled instances of Mattermost.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Vendor states this is fixed in 5.34.5 (unaffected)
Vendor states this is fixed in 5.35.4 (unaffected)
Affected range stops below 5.36.1, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (1)
CVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- REQUIRED
- Scope
- CHANGED
- Confidentiality
- LOW
- Integrity
- LOW
- Availability
- NONE
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-79
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