Zero Day MonitorZDM
DashboardVulnerabilitiesTrendingZero-DaysNewsAbout
Login
ImpressumPrivacy Policy
Zero Day Monitor © 2026
3921 articles · 228600 vulns · 37/41 feeds (7d)
← Back to list
—
CVE-2026-84458
zammad · zammad

Zammad: Account takeover via unverified email matching during SSO auto-link

Description

Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, when the "Automatic account link on initial logon" setting is enabled, Zammad binds an incoming third-party (SSO) identity to an existing local account by matching the email address the identity provider reports, without verifying that the provider actually confirmed ownership of that email. An attacker who controls any identity at a configured provider, including, by default, any Azure AD tenant via Zammad's multi-tenant Microsoft 365 /common app registration, can set that identity's email to a victim's address, authenticate, and be logged in as the victim. This bypasses the victim's local password entirely and affects any existing account, including agents and administrators. Zammad will honor the xms_edov ID token claim when email verification is required in the Microsoft 365 setting, treating a missing claim as unverified. This issue is fixed in version 7.1.2.

Affected Products

VendorProductVersions
zammadzammad< 7.1.2

References

  • https://github.com/zammad/zammad/security/advisories/GHSA-86cc-3ggh-mf2m(x_refsource_CONFIRM)
  • https://github.com/zammad/zammad/commit/0dba387df8e2b46956907975034cd44e4d021b1c(x_refsource_MISC)

Related News (1 articles)

Tier C
VulDB12d ago
CVE-2026-84458 | Zammad up to 7.1.1 Account Linking improper authentication
→ No new info (linked only)

Discussion (0)

Loading…

CISA KEV❌ No
Actively exploited❌ No
CWECWE-287
PublishedSep 25, 2026
Last enriched12d ago
Trending Score8
Source articles1
Independent1
Info Completeness7/14
Missing: cvss, epss, kev, exploit, patch, iocs, mitre_attack

Community Vote

0
Login to vote
0 upvotes0 downvotes
No votes yet

Related CVEs (5)

NONECVE-2026-102489
Undisclosed RCE in Zammad v6.3 and higher
Trending: 87
NONECVE-2026-102490
Undisclosed LPE in Zammad v1.5.0 to v7.1.0-alpha
Trending: 49
NONECVE-2026-56725
Zammad: Denial of Service via OTRS Import Controller
Trending: 8
NONECVE-2026-61525
Zammad: Arbitrary File Deletion via Unvalidated Session Identifier in Long Polling Controller
Trending: 8
NONECVE-2026-56732
Zammad: Malicious input in Ticket Body Enables Session Termination
Trending: 7

Pin to Dashboard

Verification

State: verified
Confidence: 0%

Vulnerability Timeline

CVE Published
Sep 25, 2026
Discovered by ZDM
Sep 25, 2026