CVE-2026-57522
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.
Does this matter?
Lower severity and a low EPSS score (0.46%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 4.0
- 2.3 LOWCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.46% probability · 38th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-74
- Affected
- bitwarden/server
- Source
- disclosure@vulncheck.com
References
- https://github.com/bitwarden/server/commit/a26afd18130ef985ede5c97d277820d045185a28Patch
- https://github.com/bitwarden/server/pull/7593Issue Tracking
- https://github.com/bitwarden/server/releases/tag/v2026.5.0Release Notes
- https://sanjokkarki.com.np/blog/bitwarden-webhook-json-injectionExploit, Patch, Third Party Advisory
- https://www.vulncheck.com/advisories/bitwarden-server-json-injection-via-webhook-templatesThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.