vaultwarden: Incorrect Authorization
CVE-2026-43913 is a high-severity incorrect authorization vulnerability in vaultwarden from Dani-garcia, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected vaultwarden versions: < 1.35.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.27% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of vaultwarden you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Dani-garcia | vaultwarden | < 1.35.5 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H. Scored by CNA (github.com).
Official description
Vaultwarden is a Bitwarden-compatible server written in Rust. Prior to 1.35.5, Vaultwarden allows an unconfirmed organization owner to purge the entire organization vault. The organization invite flow uses a two-step process: accepting an invite transitions membership from Invited to Accepted, and a separate confirmation by an existing owner upgrades it to Confirmed. The POST /api/ciphers/purge endpoint uses plain Headers and only checks that the membership type is Owner without verifying that the membership status is Confirmed. An authenticated user who has been invited as an organization owner and has accepted the invite and has not yet been confirmed can call this endpoint to hard-delete all ciphers and attachments in the organization, causing immediate organization-wide data loss. This vulnerability is fixed in 1.35.5.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Authorization
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
How developers prevent this class of flaw
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/dani-garcia/vaultwarden/security/advisories/GHSA-937x-3j8m-7w7pExploit, Mitigation
Other vulnerabilities in vaultwarden
- 8.1 High severity
- 7.7 High severity
- 8.3 High severity
- 9.8 Critical severity
- 8.7 High severity
- 8.1 High severity
Recent Incorrect Authorization vulnerabilities
- 7.8 High severity
- 7.5 High severity
- 8.8 High severity
- 7.3 High severity
- 9.0 Critical severity
- 8.1 High severity
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