Cyber Resilience

CVE-2025-64103

Auth Bypass in Zitadel 2.53.6 – 2.53.9

Published
29 October 2025
Modified
04 November 2025
Patch / advisory
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0033 26th percentile
Risk Priority 38 floored blend · peak EPSS

Summary

CVE-2025-64103 is a high-severity Improper Authentication (CWE-287) vulnerability in Zitadel Zitadel. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Password Spraying (T1110.003); ranked at the 26th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to IA-2 (Identification and Authentication (Organizational Users)) and IA-3 (Device Identification and Authentication) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-64103 is an improper authentication vulnerability (CWE-287, CWE-308) affecting Zitadel, an open-source identity and access management system. Starting from versions 2.53.6, 2.54.3, and 2.55.0, Zitadel only enforced multi-factor authentication (MFA) if the login policy explicitly enabled requireMFA or requireMFAForLocalUsers. When users had MFA configured without these policy requirements, the system treated single-factor authenticated sessions as valid, bypassing the second factor. This weakens MFA protections and earned a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

The vulnerability enables remote attackers with no privileges or user interaction to bypass password verification entirely by targeting only the TOTP code, a six-digit value. Attackers can compromise accounts protected by 2FA, gaining unauthorized access to sessions and potentially escalating privileges within the Zitadel-managed environment.

Mitigation is available via patches in Zitadel versions 4.6.0, 3.4.3, and 2.71.18. The GitHub security advisory (GHSA-cfjq-28r2-4jv5) and fixing commit (b284f8474eed0cba531905101619e7ae7963156b) provide further details on the resolution and recommend upgrading immediately.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Starting from 2.53.6, 2.54.3, and 2.55.0, Zitadel only required multi factor authentication in case the login policy has either enabled requireMFA or requireMFAForLocalUsers. If a user has set up MFA without this requirement, Zitadel would consider single factor auhtenticated sessions…

more

as valid as well and not require multiple factors. Bypassing second authentication factors weakens multifactor authentication and enables attackers to bypass the more secure factor. An attacker can target the TOTP code alone, only six digits, bypassing password verification entirely and potentially compromising accounts with 2FA enabled. This vulnerability is fixed in 4.6.0, 3.4.3, and 2.71.18.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1110.003 Password Spraying Credential Access
Adversaries may use a single or small list of commonly used passwords against many different accounts to attempt to acquire valid account credentials.
T1021 Remote Services Lateral Movement
Adversaries may use [Valid Accounts](https://attack.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1078.001 Default Accounts Stealth
Adversaries may obtain and abuse credentials of a default account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
T1110 Brute Force Credential Access
Adversaries may use brute force techniques to gain access to accounts when passwords are unknown or when password hashes are obtained.
T1110.001 Password Guessing Credential Access
Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-64717Same product: Zitadel Zitadel
CVE-2024-49757Same product: Zitadel Zitadel
CVE-2026-29193Same product: Zitadel Zitadel
CVE-2025-46815Same product: Zitadel Zitadel
CVE-2024-32868Same product: Zitadel Zitadel
CVE-2025-64102Same product: Zitadel Zitadel
CVE-2026-23511Same product: Zitadel Zitadel
CVE-2023-49097Same product: Zitadel Zitadel
CVE-2023-44399Same product: Zitadel Zitadel
CVE-2025-64101Same product: Zitadel Zitadel

Affected Assets

zitadel
zitadel
2.53.6 — 2.53.9 · 2.54.3 — 2.54.10 · 2.55.0 — 2.71.18

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 8 hardening rules · 5 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.4.4
  • V6.5.4
  • V6.5.5
  • V6.5.7

Mitigating Controls (NIST 800-53 r5) AI

Mandates unique identification and authentication of organizational users before access, directly stopping improper authentication.

Requires unique identification and authentication of devices before establishing connections, preventing unauthenticated device claims.

Mandates unique identification and authentication of non-organizational users, directly addressing the weakness for external actors.

Manages authenticators with verification and secure distribution, reducing opportunities for improper authentication.

Enforces access only after approved authorizations, which presupposes correct authentication has occurred.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 full match
prevents

Explicit MFA requirement directly eliminates single-factor authentication while the control also addresses broader authentication scope.

PR.AA-04 mostly match
prevents

PR.AA-04 directly enables verification of identity assertions (mostly preventing CWE-287 in that scope) yet leaves many other authentication failure modes unaddressed (only partial prevention overall).

PR.AA-01 partial match
prevents

PR.AA-01 supplies and governs credentials/tokens that authentication relies on, removing some weak-credential cases, yet leaves verification logic, missing checks, and protocol flaws untouched.

PR.AA-02 partial match
prevents

PR.AA-02 ensures valid enrollment and unique credential binding, which reduces some improper-auth risks at issuance time but leaves runtime claim verification untouched, so each direction only partially addresses the other.

PR.PS-01 partial match
prevents

PR.PS-01 can enforce auth-related settings via hardened baselines and default reviews, blocking some config-based instances of CWE-287, yet leaves code-level auth flaws untouched so neither direction reaches mostly.

PR.PS-02 partial match
prevents

Patching/maintenance can remediate some known auth vulnerabilities after deployment (partial forward) but does not address the design or implementation of authentication logic itself (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring authentication methods whose strength matches the sensitivity of the data and mandating multi-factor authentication directly blocks attempts to access resources without proving identity.

prevents

Verifying user identity before issuing replacement credentials and forcing changes after compromise reduces the likelihood that authentication bypass can be achieved through stolen or weak credentials.

prevents

Access control policy can mandate multi-factor authentication but does not prescribe the technical implementation.

prevents

Mandating segregated approval and oversight for non-human identities reduces the chance that weak or orphaned credentials can be exploited for unauthorized authentication.

degrades

Access rights provisioning can require MFA, yet the control is broader than authentication strength.

degrades

Privileged access rights can be conditioned on MFA, but the control focuses on privilege scope rather than factor count.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-287
RHEL 7 (3 rules)
  • V-204425 The Red Hat Enterprise Linux operating system must be configured so that the SSH daemon does not allow authentication using an empty password. prevents CWE-287
  • V-204442 The Red Hat Enterprise Linux operating system must not have the rsh-server package installed. prevents CWE-287
  • V-204424 The Red Hat Enterprise Linux operating system must not allow accounts configured with blank or null passwords. prevents CWE-287
RHEL 8 (1 rule)
  • V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-287
Ubuntu 22.04 (1 rule)
  • V-260470 Ubuntu 22.04 LTS, when booted, must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
Ubuntu 24.04 (2 rules)
  • V-270675 Ubuntu 24.04 LTS when booted must require authentication upon booting into single-user and maintenance modes. prevents CWE-287
  • V-270714 Ubuntu 24.04 LTS must not allow accounts configured in Pluggable Authentication Modules (PAM) with blank or null passwords. prevents CWE-287

References