Medium SSRF

CVE-2026-34719 — Zammad has a Server-side request forgery (SSRF) via webhooks

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1 and 6.5.4, the webhook model was missing a proper validation for loop back addresses, or link-local addresses — only the URL scheme (HTTP/HTTPS) as well as the hostname was checked. This could end up in retrieving confidential metadata of cloud/hosting providers. The existing check is now extended and is applied when configuring webhooks as well as triggering webhook jobs. This vulnerability is fixed in 7.0.1 and 6.5.4.

Published Apr 8, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.3% (30-day exploitation probability)+3
Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.3%

ahead of 21% of scored CVEs · Oct 14, 2026

Affects

Zammad

CVSS base

4.3

Medium · 5 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Zammad Zammad).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes matching the vulnerability class (ssrf), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Zammad	Zammad	< 6.5.4version 7.0.0	Vulnerable	NIST National Vulnerability Database
Zammad	Zammad	version < 6.5.4version >= 7.0.0-alpha, < 7.0.1	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
8.3	CVSS 4.0	High	—	—	security-advisories@github.com via NIST National Vulnerability Database
8.3	CVSS 4.0	High	—	—	GitHub_M via CVE Program (cve.org) e CISA ADP
4.3	CVSS 3.1	Medium	2.8	1.4	nvd@nist.gov via NIST National Vulnerability Database
4.3	CVSS 3.1	Medium	2.8	1.4	134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database
4.3	CVSS 3.1	Medium	—	—	CISA-ADP via CVE Program (cve.org) e CISA ADP

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-918 · Server-Side Request Forgery (SSRF)

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.30%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Monitor outbound requests from the server to internal IPs and cloud metadata endpoints.

web/proxy/WAF logsnetwork IDS/IPSegress traffic

Timeline

What happened to this CVE, newest first.

2026
Affected products added · zammad/zammad
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 13, 2026
CVSS changed · 4.3
Oct 13, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
CVE published
Apr 8, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

github.com/zammad/zammad/security/advisories/GHSA-2vgc-vfh2-rw75
Vendor Advisory, x_refsource_CONFIRM, NIST National Vulnerability Database

Elsewhere on this site

Zammad
every CVE for this vendor

SSRF
same class

CWE-918
other pages naming this weakness

Related CVEs (same products)

High CVE-2026-102490 Zammad GmbH Zammad Improper Privilege Management Vulnerability KEV 15d
Critical CVE-2026-102489 Zammad GmbH Zammad Session Fixation Vulnerability KEV 15d
Medium CVE-2026-34837 Zammad is miissing authorization in AI assistance controller for context data used in text tools Apr 8, 2026
Medium CVE-2026-34720 Zammad has an origin validation error in SSO mechanism Apr 8, 2026
Medium CVE-2026-34721 Zammad has Cross-site request forgery (CSRF) in OAuth callback endpoints Apr 8, 2026
Medium CVE-2026-34722 Zammad is missing authorization in ticket create endpoint Apr 8, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-34719 is "Zammad has a Server-side request forgery (SSRF) via webhooks", rated Medium. It affects Zammad (Zammad); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.3 describes technical severity. EPSS 0.30% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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