CVE-2026-43638: bitwarden server · Missing Authorization
Affects bitwarden serverSource CVE Database V5
Not known to be exploited · CVSS 5.3 Medium : upgrade to 2026.4.1 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2026.4.1
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 11 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade bitwarden/server and server to 2026.4.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| bitwardenserver | Affected
| Fixed in– |
GitHubbitwarden/serverpkg:github/bitwarden/serverOther threats | Affected
| Fixed in
|
GitHubserverpkg:github/serverOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, restrict authenticated user permissions and monitor for suspicious activity related to the /ciphers/import-organization endpoint.
Description
Bitwarden Server prior to v2026.4.1 contains a missing authorization vulnerability that allows any authenticated user to write ciphers into an arbitrary organization via `POST /ciphers/import-organization` by submitting an empty `collections` array, which causes the server-side permission check to be skipped.
References
- sanjokkarki.com.np/blog/bitwarden-import-org-bypass (opens in a new tab)
- github.com/bitwarden/server/releases/tag/v2026.4.1 (opens in a new tab)
- github.com/bitwarden/server/pull/7394 (opens in a new tab)
- github.com/bitwarden/server/commit/ebbf6dd0fa752114c09d73abb48ce32a50476758 (opens in a new tab)
- vulncheck.com/advisories/bitwarden-server-missing-authorization-via-organization-cipher-import (opens in a new tab)