PT-2026-52576 · Bitwarden · Server

Sanjok Karki · Published 2026-06-25 · Updated 2026-06-25 · CVE-2026-57522

Mitre

CVSS v3.1

3.5

Low

Base vector

AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N

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.

Exploit

Fix

Special Elements Injection

Weakness Enumeration

CWE-74

Related Identifiers

CVE-2026-57522

Affected Products

Server

References · 6

• 🔥 https://sanjokkarki.com.np/blog/bitwarden-webhook-json-injection · Exploit
• https://github.com/bitwarden/server/commit/a26afd18130ef985ede5c97d277820d045185a28 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-57522 · Security Note
• https://github.com/bitwarden/server/pull/7593 · Note
• https://github.com/bitwarden/server/releases/tag/v2026.5.0 · Note
• https://vulncheck.com/advisories/bitwarden-server-json-injection-via-webhook-templates · Note