CVE-2026-57522

Bitwarden Server < 2026.5.0 JSON Injection via Webhook Templates

MEDIUM
5
CVSS Score
Published: June 25, 2026 at 07:09 PM UTC
Updated: October 25, 2026 at 10:10 PM UTC
1 product affected across 1 vendorServer

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Severity
MEDIUM5
Exploit prediction
EPSS 0.5%
SSVC
PoC

Description

Bitwarden Server before 2026.5.0 contains a JSON injection vulnerability in IntegrationTemplateProcessor.ReplaceTokens(), which substitutes user-controlled values into event-integration templates without JSON encoding. When an organization has configured an event integration whose template references a user-controlled token (such as #ActingUserName# or #UserName#, populated from a member's display name), an authenticated member can set their display name to JSON metacharacters and inject arbitrary key-value pairs into the rendered payloads delivered to webhook, SIEM, Slack, Teams, or Datadog endpoints, making injected fields indistinguishable from legitimate template output.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2026.5.0
Affected range stops below 2026.5.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-74

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