NVD / CVE Program· CNA GitHub_M

CVE-2026-85056: ZITADEL: MFA bypass via session reuse in Login V2

HighCVSS 8.2 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 32/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.28% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
According to CISA the attack is automatable: targets can be found by mass scanning.
Fixed version: zitadel zitadel 4.16.1.
Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to zitadel zitadel 4.16.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

ZITADEL is an open source identity management platform. From 4.0.0 until 4.16.1, ZITADEL Login V2 creates a browser session after password verification and can reuse that session for a later authentication request without verifying a user's enrolled TOTP, OTP, or U2F second factor. When the MFA step is abandoned and login starts again, session-validity checks require MFA only when the organization enables Force MFA or Force MFA for local users only, so a voluntarily enrolled factor can be skipped while completing an OIDC or SAML callback for a customer application. Login V1, the ZITADEL Console, Management and Admin APIs, and user self-management are not affected. This issue is fixed in version 4.16.1.

Published: Sep 24, 2026
Updated: Sep 28, 2026
EPSS: 0.2% · 21th percentile
CWE: CWE-287

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 32 / 40 · 8.2 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: yes
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · GitHub_M: 8.2; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

zitadel zitadel
- >= 4.0.0, < 4.16.1affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Go	github.com/zitadel/zitadel	before 1.80.0-v2.20.0.20260717062356-56f4798ed31f	1.80.0-v2.20.0.20260717062356-56f4798ed31f

Same product

zitadel: all records

Other highest-scoring records for the same primary product.

CVE-2026-109372ZITADEL 3.0.0 before 4.19.2 Account Takeover via SAML Identity-Provider Confusion
37Monitor
CVE-2026-105215ZITADEL before 4.16.2 Account Pre-Hijacking via Forged External IdP Callback
37Monitor
CVE-2026-105209ZITADEL before 3.4.15 and 4.17.1 Cross-Organization Account Takeover via Passkey Enrollment
37Monitor

Published before and after this one in the same product

← EarlierCVE-2026-54693Jul 29, 2026 · ZITADEL Users Can Self-Verify Email/Phone via API
32Monitor
← EarlierCVE-2026-76081Sep 14, 2026 · ZITADEL: Improper Role Revocation on Granted Projects during Multiple Role Deletions
22Monitor
Later →CVE-2026-85057Sep 24, 2026 · ZITADEL: Actions V1 sandbox escape: host file read via require()
34Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
zitadel zitadel	4.16.1 · description	Vendor (CNA)
Go:github.com/zitadel/zitadel	1.80.0-v2.20.0.20260717062356-56f4798ed31f	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2026-10937218 days apartZITADEL 3.0.0 before 4.19.2 Account Takeover via SAML Identity-Provider Confusion
37Monitor
CVE-2026-10521010 days apartZITADEL before 4.17.1 Unauthenticated MFA Enrollment via Login V1 Init Handlers
35Monitor
CVE-2026-10521310 days apartZITADEL before 4.17.1 Authentication Bypass via Login V2 for Deactivated Organizations
35Monitor
CVE-2026-10521210 days apartZITADEL before 3.4.14 and 4.16.2 Account Takeover via Passkey Enrollment
34Monitor
CVE-2025-64103330 days apartZitadel Bypass Second Authentication Factor
34Monitor
CVE-2026-29193201 days apartZITADEL: Bypassing Zitadel Login Behavior and Security Policy in Login V2
32Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

CVE-2026-850570 days apartZITADEL: Actions V1 sandbox escape: host file read via require()
34Monitor
CVE-2026-10521410 days apartZitadel before 4.16.2 SSRF via Organization Domain HTTP Verification
9Monitor
CVE-2026-5567176 days apartZITADEL: Server-Side Request Forgery (SSRF) and Denylist Bypass in Outgoing HTTP Components
9Monitor

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-26-1176 · Sep 25, 2026(ZITADEL Güvenlik Zafiyeti)

All national notices →

Not on record for this CVE: researcher credit · public bounty program.

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: low · data or configuration can be modified
Availability: none

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: Low
Availability impact: None

Weakness class (CWE)

CWE-287 · Improper Authentication

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

nvd-secondary

Root cause

Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.

The bug in code

The whole CWE-287 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1app.use("/admin", requireSession, adminRouter);
2

3// Route added later skips the middleware
4app.post("/admin-api/config", updateConfig);

Fixed

1const admin = express.Router();
2admin.use(requireSession, requireRole("admin"));
3

4admin.post("/config", updateConfig);
5app.use("/admin", admin);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

Change log (2)

Fix✗ → ✓Sep 28, 2026, 10:45 PM UTC
SSVC exploitation— → noneSep 28, 2026, 8:49 PM UTC

For records you follow, these changes also arrive as notifications. →

References

github.com/zitadel/zitadel/commit/049dbb25a56587fb3980c85c99819cad69f637db

Show all references (3 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records