CVE-2026-57522: Bitwarden Server < 2026.5.0 JSON Injection via Webhook Templates
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.
Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N · CWE-74
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
bitwarden: server
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/bitwarden/server/commit/a26afd18130ef985ede5c97d277820d045185a28 (opens in new tab)
- github.com/bitwarden/server/pull/7593 (opens in new tab)
- github.com/bitwarden/server/releases/tag/v2026.5.0 (opens in new tab)
- sanjokkarki.com.np/blog/bitwarden-webhook-json-injection (opens in new tab)
- www.vulncheck.com/advisories/bitwarden-server-json-injection-via-webhook-templates (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)