CVE-2026-84463Network attack vectorHinoki check available

Forced session switching via unescaped iframe attribute

Published Sep 25, 2026 · Updated Sep 25, 2026

Stored HTML injection in Zammad before 7.1.2 allows remote authenticated users to force another user's session switch. The Knowledge Base video widget inserts a crafted value into an iframe attribute without context-appropriate escaping, allowing injected HTML to issue a session-switch request. Exploitation requires category editing rights and a viewer permitted to switch sessions; merely opening the published answer changes the viewer to the attacker's chosen account.

CVSS severity6.3
Medium
EPSS probability0.15%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stored HTML injection in Zammad before 7.1.2 allows remote authenticated users to force another user's session switch. The Knowledge Base video widget inserts a crafted value into an iframe attribute without context-appropriate escaping, allowing injected HTML to issue a session-switch request. Exploitation requires category editing rights and a viewer permitted to switch sessions; merely opening the published answer changes the viewer to the attacker's chosen account.

The record

CVE
CVE-2026-84463
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
Zammad GmbH
Product
Zammad
Classifications
CWE-79, CWE-838, CWE-352
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 7.1.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Zammad GmbH · Zammadversion=< 7.1.2

Published CVSS scores

6.3ZammadCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-838Inappropriate Encoding for Output Context
CWE-352Cross-Site Request Forgery (CSRF)

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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