zitadel: Reliance on Cookies without Validation and Integrity Checking
CVE-2026-119128 is a high-severity reliance on cookies without validation and integrity checking vulnerability in zitadel, with a CVSS 3.1 base score of 7.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 4.19.5 as the first without the flaw, so updating zitadel to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.29% 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
- Update zitadel to 4.19.5 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
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
- HighSuccess depends on conditions outside the attacker's control.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.1 | Critical | CNA (vulncheck.com) |
| CVSS 3.1 | 7.4 | High | CNA (vulncheck.com) |
Official description
ZITADEL 4.0.0 before 4.19.5 contains an authentication bypass vulnerability in the Login V2 UI that allows unauthenticated attackers to set the first credential of users lacking any authentication method. Attackers can compute a valid verificationCheck cookie from the user ID and browser fingerprint to set a password, register a passkey, or link an identity provider, taking over the account.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Reliance on Cookies without Validation and Integrity Checking
The product relies on the existence or values of cookies when performing security-critical operations, but it does not properly ensure that the setting is valid for the associated user.
How developers prevent this class of flaw
- Avoid using cookie data for a security-related decision.
- Perform thorough input validation (i.e.: server side validation) on the cookie data if you're going to use it for a security related decision.
- Add integrity checks to detect tampering.
More Reliance on Cookies without Validation and Integrity Checking vulnerabilities (CWE-565)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in zitadel
- 8.1 High severity
- 8.1 High severity
- 8.1 High severity
- 8.7 High severity
- 8.2 High severity
- 9.1 Critical severity
Recent Reliance on Cookies without Validation and Integrity Checking vulnerabilities
- 9.8 Critical severity
- 9.3 Critical severity
- 9.1 Critical severity
- 9.8 Critical severity
- 8.3 High severity
- 8.1 High severity
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