Medium · CVSS 5.1CVE-2026-116280

Kameleo Proxy Validation f.cs InternalController.TestProxy server-side request forgeryCVE-2026-116280

Answer in brief

CVE-2026-116280 records a Medium severity (CVSS 5.1) vulnerability in Kameleo Proxy Validation f.cs InternalController.TestProxy server-side request forgery. The current sources do not mark it as known exploited. The current feed maps n/a/Kameleo (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 26, 2026Updated Oct 26, 2026Source checked Oct 26, 2026First seen by HOL Oct 26, 2026Material review Oct 26, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.1
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 5.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps n/a/Kameleo (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
n/a/Kameleogeneric	5.0.1.0 \|\| 5.0.1.1 \|\| 5.0.1.2 \|\| 5.0.1.3 \|\| 5.0.1.4 \|\| 5.0.1.5 \|\| 5.0.1.6 \|\| 5.0.1.7 \|\| 5.0.1.8 \|\| 5.0.1.9 \|\| 5.0.1.10 \|\| 5.0.1.11 \|\| 5.0.1.12 \|\| 5.0.1.13 \|\| 5.0.1.14 \|\| 5.0.1.15 \|\| 5.0.1.16 \|\| 5.0.1.17 \|\| 5.0.1.18 \|\| 5.0.1.19 \|\| 5.0.1.20 \|\| 5.0.1.21 \|\| 5.0.1.22 \|\| 5.0.1.23 \|\| 5.0.1.24 \|\| 5.0.1.25 \|\| 5.0.1.26	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for n/a/Kameleo.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Oct 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Oct 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Oct 26, 2026

Sources and claim methodology

Upstream source description

A vulnerability was determined in Kameleo up to 5.0.1.26. Affected is the function InternalController.TestProxy of the file client-engine-application/f.cs of the component Proxy Validation. Executing a manipulation of the argument host/port can lead to server-side request forgery. The attack may be launched remotely. Upgrading to version 5.2.0 is able to address this issue. It is suggested to upgrade the affected component. The route has been removed and replaced with /general/test-proxy in 5.2.0.

Quoted source text, attributed separately from HOL analysis.

Mattermost OpenID discovery endpoint request bypasses outbound connection filtering, allowing SSRF by a System AdministratorAlso CWE-918