---
title: "CVE-2021-27312: Gleez Cms Server Side Request Forgery (SSRF) vulnerability"
url: https://erroneo.us/security/cve/CVE-2021-27312/
description: "CVE-2021-27312 (gleez/cms (Composer (PHP))): Server Side Request Forgery (SSRF) vulnerability in Gleez Cms 1.2.0, allows remote attackers to execute…"
type: vulnerability-record
section: "Security Digest"
date_published: 2024-04-03
date_modified: 2024-08-28
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2021-27312"
kev: false
cvss: 9.4
epss: 0.01031
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2021-27312: Gleez Cms Server Side Request Forgery (SSRF) vulnerability

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 1.0% , percentile 63: FIRST’s model estimates a 1.0% chance of exploitation activity in the next 30 days, higher than 63% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes gleez/cms (Composer (PHP)) <= 1.2.0, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

Server Side Request Forgery (SSRF) vulnerability in Gleez Cms 1.2.0, allows remote attackers to execute arbitrary code and obtain sensitive information via modules/gleez/classes/request.php.

## Affected packages

- Composer (PHP) `gleez/cms` <= 1.2.0 → fixed: none listed

## Affected products (CVE record)

- n/a n/a: see advisory

## Severity

- CISA-ADP CVSS 3.1: 9.4 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L`
- GitHub CVSS 3.1: 9.0 `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 1.03% probability of exploitation activity in the next 30 days; percentile 63.

## Sources

- [GitHub Advisory GHSA-7mxg-r76p-363g](https://github.com/advisories/GHSA-7mxg-r76p-363g)
- [CVE.org record CVE-2021-27312](https://www.cve.org/CVERecord?id=CVE-2021-27312)
- [NVD entry CVE-2021-27312](https://nvd.nist.gov/vuln/detail/CVE-2021-27312)
- [github.com](https://github.com/gleez/cms/issues/805)
- [gist.github.com](https://gist.github.com/LioTree/8d10d123d31f50db05a25586e62a87ba)

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Source page: https://erroneo.us/security/cve/CVE-2021-27312/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt