CyberSecBulletin
CVE-2025-46815NVD status: Analyzed

zitadel: Authentication Bypass by Capture-replay

Published Updated By the CyberSecBulletin desk

CVE-2025-46815 is a high-severity authentication bypass by capture-replay vulnerability in zitadel, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected zitadel versions: >= 3.0.0-rc.1, < 3.0.0; < 2.70.10; >= 2.71.0, < 2.71.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.47% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of zitadel you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Zitadelzitadel>= 3.0.0-rc.1, < 3.0.0; < 2.70.10; >= 2.71.0, < 2.71.9Not 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
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:R/S:C/C:H/I:H/A:N. Scored by CNA (github.com).

Official description

The identity infrastructure software ZITADEL offers developers the ability to manage user sessions using the Session API. This API enables the use of IdPs for authentication, known as idp intents. Following a successful idp intent, the client receives an id and token on a predefined URI. These id and token can then be used to authenticate the user or their session. However, prior to versions 3.0.0, 2.71.9, and 2.70.10, it was possible to exploit this feature by repeatedly using intents. This allowed an attacker with access to the application’s URI to retrieve the id and token, enabling them to authenticate on behalf of the user. It's important to note that the use of additional factors (MFA) prevents a complete authentication process and, consequently, access to the ZITADEL API. Versions 3.0.0, 2.71.9, and 2.70.10 contain a fix for the issue. No known workarounds other than upgrading are available.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Authentication Bypass by Capture-replay

A capture-replay flaw exists when the design of the product makes it possible for a malicious user to sniff network traffic and bypass authentication by replaying it to the server in question to the same effect as the original message (or with minor changes).

How developers prevent this class of flaw

  • Utilize some sequence or time stamping functionality along with a checksum which takes this into account in order to ensure that messages can be parsed only once.
  • Since any attacker who can listen to traffic can see sequence numbers, it is necessary to sign messages with some kind of cryptography to ensure that sequence numbers are not simply doctored along with content.

More Authentication Bypass by Capture-replay vulnerabilities (CWE-294)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in zitadel

All zitadel vulnerabilities

Recent Authentication Bypass by Capture-replay vulnerabilities

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