Is CVE-2021-47958 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2021-47958 being exploited in the wild.

How severe is CVE-2021-47958?

Medium severity, with a CVSS score of 4.3, published 15 May 2026.

Is there a fix for CVE-2021-47958?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2021-47958 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2021-47958?

Check whether you run Couchcms at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2021-47958: CouchCMS SSRF via SVG upload in browse.php

CVE-2021-47958 · Severity: medium · CVSS 4.3 · Published 2026-05-15

CouchCMS, a content management system designed for web designers, is vulnerable to a security flaw that allows logged-in users to perform unauthorized network requests. By uploading a specially crafted image file, an attacker could force the server to interact with internal systems or external websites. This could be used to probe internal network services that are not normally accessible from the internet.

Technologies: Couchcms. Vendors: Couchcms.

Quick answers

Is CVE-2021-47958 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2021-47958 being exploited in the wild.
How severe is CVE-2021-47958?: Medium severity, with a CVSS score of 4.3, published 15 May 2026.
Which products and versions are affected?: Couchcms 2.2.1 and earlier.
Is there a fix for CVE-2021-47958?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2021-47958 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2021-47958?: Check whether you run Couchcms at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A Server-Side Request Forgery (SSRF) vulnerability exists in CouchCMS version 2.2.1 and earlier. The flaw is located in the KCFinder component, specifically within the `browse.php` endpoint used for file management. Authenticated attackers can upload malicious SVG files containing external entity references or image tags with remote `xlink:href` attributes. When the server processes these files, it attempts to fetch the remote resources, allowing the attacker to make arbitrary HTTP requests from the server's IP address. This can be leveraged to scan internal networks, bypass firewalls, or interact with internal services.

Affected products

CouchCMS CouchCMS 2.2.1 and earlier

Timeline

2021-01-25: disclosed: Vulnerability discovered and reported by xxcdd
2021-03-19: other: Exploit code published on Exploit-DB
2026-05-15: advisory: CVE published/updated in NVD dataset

References

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