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TI-2026-82645 Aliases CVE-2026-119127GHSA-47m4-8jqx-5r73

Host header injection in ZITADEL Login V2 enables account takeover

Priority LOW 39CWE-640Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-640.

Summary

ZITADEL versions 4.0.0 before 4.19.5 contain a host header injection flaw in the Login V2 UI, tracked as CWE-640 (weak password recovery mechanism for forgotten password). An unauthenticated attacker who knows a victim's login name can supply untrusted x-zitadel-public-host, x-zitadel-forward-host, or x-forwarded-host headers so that password-reset, invite, and email-verification links in genuine emails point to the attacker's host. When a victim opens such a link, the attacker can harvest the single-use code and take over the account, including instance administrator accounts. Exploitation is not reported in CISA KEV or by a public exploit link.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

ZITADEL 4.0.0 before 4.19.5 contains a host header injection vulnerability in the Login V2 UI that allows unauthenticated attackers to poison password-reset, invite, and email-verification links by supplying untrusted x-zitadel-public-host, x-zitadel-forward-host, or x-forwarded-host headers. Attackers knowing a victim's login name can point the links in genuine emails at their host, harvest the single-use codes when the links are opened, and take over accounts including instance administrators.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00278 20th percentileScored 2026-11-07
Fix Fixed zitadel (zitadel): 4.19.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
zitadelzitadel4.0.0 to before 4.19.54.19.5Patch availableCNA
  • zitadel Vendorzitadel Affected 4.0.0 to before 4.19.5 Fixed in 4.19.5 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:*——zitadel
  • cpe:2.3:a:zitadel:zitadel:*:*:*:*:*:*:*:* Versions — — ·zitadel

Remediation

Upgrade ZITADEL to version 4.19.5. Versions from 4.0.0 before 4.19.5 are affected.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

  • Fix · CNA zitadel (zitadel) Fixed in 4.19.5

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    zitadel 4.19.5

    3 records Highest priority Priority MEDIUM 2 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-82647 ZITADEL Login V2 flaw lets attackers approve device authorizationsPriority MEDIUM 45
    • TI-2026-82646 Authentication bypass in ZITADEL Login V2 enables account takeoverPriority MEDIUM 41
    Show all 3 records →

Timeline

  1. 2026-10-29 Threatist record created from CVE-2026-119127
  2. 2026-10-29 Alias added: GHSA-47m4-8jqx-5r73
  3. 2026-10-31 Priority changed: MEDIUM → LOW
  4. 2026-11-04 CISA SSVC decision points changed

References

Advisory 1

  • TI-2024-26607 ZITADEL Vulnerable to Session Information Leakage CVSS 3.1MEDIUM 6.5
  • TI-2026-67551 ZITADEL before 4.16.2 Account Pre-Hijacking via Forged External IdP Callback CVSS 4.0CRITICAL 9.3
  • TI-2026-67543 ZITADEL before 4.17.3 Account Takeover via External IdP Linking CVSS 4.0CRITICAL 9.3
  • TI-2025-41253 ZITADEL Vulnerable to Unauthenticated Full-Read SSRF via V2 Login CVSS 3.1CRITICAL 9.3
  • TI-2025-39554 Zitadel Bypass Second Authentication Factor CVSS 4.0HIGH 8.7
  • TI-2026-82647 ZITADEL Login V2 flaw lets attackers approve device authorizations CVSS 4.0HIGH 8.6
See all 77 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences