CVE-2026-34837: Zammad is a web based open source helpdesk/customer support system

Routine

MEDIUM 4.3DOWNGRADE

CVE-2026-34837 is a medium-severity flaw (CVSS 4.3) affecting zammad. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1, he REST endpoint POST /api/v1/ai_assistance/text_tools/:id contains an authorization failure. Context data (e.g., a group or organization) supplied to be used in the AI prompt were not checked if they are accessible for the current user. This leads to having data present in the AI prompt that were not authorized before being used. A user needs to have ticket.agent

Why this priority

No elevated risk signals yet

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	4.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.2% (top 93%)
CISA exploited list	No
Weakness	CWE-862
Published	2026-04-08
Last modified	2026-07-24

Publisher (CNA): GitHub, Inc. · Vendor: zammad

Last updated 2026-07-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-04-08 19:25 UTCPublished CVE record published
2026-07-24 22:10 UTCUpdated Record last modified

zammad zammad DOWNGRADE

Affected: 7.0.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 7.0.0

1. Check installed version

apt-cache policy zammad || rpm -q zammad || zammad --version

2. No fixed release: DOWNGRADE to a release before 7.0.0 (Debian / Ubuntu)

apt-cache madison zammad sudo apt install zammad=<VERSION_BEFORE_7.0.0> sudo apt-mark hold zammad

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list zammad sudo dnf downgrade zammad-<VERSION_BEFORE_7.0.0> sudo dnf versionlock add zammad

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-34837?

zammad: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2026-34837 being exploited?

CVE-2026-34837 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-34837 affect?

CVE-2026-34837 affects zammad. Severity is medium (CVSS 4.3). Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1, he REST endpoint POST /api/v1/ai_assistance/text_tools/:id contains an authorization failure. Context data (e.g., a group or organization) supplied to be us

How urgent is CVE-2026-34837?

Priority 17/100. No elevated risk signals yet.

Related CVEs

CVE-2026-102489 CRITICAL 9.8 EXPLOITED UPGRADE Zammad GmbH Zammad Session Fixation Vulnerability
CVE-2026-102490 HIGH 7.8 EXPLOITED UPGRADE Zammad GmbH Zammad Improper Privilege Management Vulnerability
CVE-2026-34723 HIGH 7.5 UPGRADE Zammad is a web based open source helpdesk/customer support system
CVE-2026-34724 HIGH 7.2 DOWNGRADE Zammad is a web based open source helpdesk/customer support system
CVE-2026-34721 MEDIUM 6.5 UPGRADE Zammad is a web based open source helpdesk/customer support system

References

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