JSON Injection Vulnerability in Bitwarden Server from Bitwarden
CVE-2026-57522

2.3LOW

Key Information:

Vendor

Bitwarden

Status
Server
Vendor
CVE Published:
25 June 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-57522?

Bitwarden Server versions prior to 2026.5.0 are susceptible to a JSON injection vulnerability in the IntegrationTemplateProcessor.ReplaceTokens() method. This flaw allows authenticated users to introduce JSON metacharacters into event integration templates, specifically tokens that are derived from user-controlled fields such as display names. As a result, it is possible for malicious users to inject arbitrary key-value pairs into the payloads sent to external services like webhooks, SIEM, Slack, Teams, or Datadog. This makes it difficult to distinguish between legitimate data and any injected content, posing a significant risk to the integrity and security of the information being transmitted.

Affected Version(s)

server 0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-57522 - Proof of Concept

References

https://sanjokkarki.com.np/blog/bitwarden-webhook-json-in...
technical-descriptionexploit
https://github.com/bitwarden/server/releases/tag/v2026.5.0
release-notes
https://github.com/bitwarden/server/pull/7593
issue-tracking

CVSS V4

Score:
2.3
Severity:
LOW
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Sanjok Karki
.