CVE-2026-42346Network attack vector

Unauthenticated SSRF via DNS rebinding race

Published May 8, 2026 · Updated May 8, 2026

SSRF in GitroomHQ Postiz 2.16.6 through 2.21.6 allows remote attackers to reach internal network addresses via DNS rebinding. The isSafePublicHttpsUrl() validator approves a resolved public address, but later fetch() calls independently resolve the hostname without binding that result. Control of the target hostname's DNS enables blind internal host and port probing and attacker-influenced POST requests without authentication.

CVSS severity6.5
Medium
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in GitroomHQ Postiz 2.16.6 through 2.21.6 allows remote attackers to reach internal network addresses via DNS rebinding. The isSafePublicHttpsUrl() validator approves a resolved public address, but later fetch() calls independently resolve the hostname without binding that result. Control of the target hostname's DNS enables blind internal host and port probing and attacker-influenced POST requests without authentication.

The record

CVE
CVE-2026-42346
Published
May 8, 2026
Updated
May 8, 2026
Vendor
GitroomHQ
Product
Postiz
Classifications
CWE-918, T1046
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 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=>= 2.16.6, < 2.21.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GitroomHQ · Postizversion=>= 2.16.6, < 2.21.7

Published CVSS scores

6.5GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A: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.

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

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1046Network Service Discovery

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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