CVE-2026-57522CWE-74

Bitwarden Server < 2026.5.0 JSON Injection via Webhook Templates

Low · published June 25, 2026

CVSS v4.0
2.3
EPSS
0%
Percentile
38.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
2.3 · LOW
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
EPSS
0.00455 · 38.5th percentile
Weakness
CWE-74 · Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Published
2026-06-25T19:09Z
EPSS history
Timeline
  • 25 JUN 19:09Z
    Bitwarden Server < 2026.5.0 JSON Injection via Webhook Templates
    cvelistv5