Low 3.5Published Jun 25, 2026

CVE-2026-57522Bitwarden Server < 2026.5.0 JSON Injection via Webhook Templates

Updated under an hour ago (Oct 27, 2026, 9:40 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for bitwarden server

Exploited in the last 30 days

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: 3.5 LOW (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N
Weakness (CWE): CWE-74
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Analyzed
Record last updated: Jul 14, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

bitwarden server bitwarden:server (from the name)	before 2026.5.0	CNA record
bitwarden server bitwarden:server	before 2026.5.0	NVD

References

References

https://sanjokkarki.com.np/blog/bitwarden-webhook-json-injection	technical-description, exploit, patch, third-party-advisory
https://github.com/bitwarden/server/releases/tag/v2026.5.0	release-notes
https://github.com/bitwarden/server/pull/7593	issue-tracking
https://github.com/bitwarden/server/commit/a26afd18130ef985ede5c97d277820d045185a28	patch
https://www.vulncheck.com/advisories/bitwarden-server-json-injection-via-webhook-templates	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.