CVE-2021-27312: Server Side Request Forgery (SSRF) vulnerability in Gleez Cms 1.2.0, allows remote attackers to execute arbitr

This week

CRITICAL 9.4REMOTEDOWNGRADE

CVE-2021-27312 is a critical-severity flaw (CVSS 9.4) affecting gleez cms. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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.

Why this priority

Critical severity
Public exploit reference
Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	9.4 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	1.0% (top 36%)
CISA exploited list	No
Weakness	CWE-918
Published	2024-04-03
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: gleezcms

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2024-04-03 06:15 UTCPublished CVE record published
2026-06-17 03:44 UTCUpdated Record last modified

gleezcms gleez cms DOWNGRADE

Affected: 1.2.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.2.0

1. Check installed version

apt-cache policy gleez-cms || rpm -q gleez-cms || gleez-cms --version

2. No fixed release: DOWNGRADE to a release before 1.2.0 (Debian / Ubuntu)

apt-cache madison gleez-cms sudo apt install gleez-cms=<VERSION_BEFORE_1.2.0> sudo apt-mark hold gleez-cms

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list gleez-cms sudo dnf downgrade gleez-cms-<VERSION_BEFORE_1.2.0> sudo dnf versionlock add gleez-cms

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2021-27312?

gleez cms: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2021-27312 being exploited?

CVE-2021-27312 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2021-27312 affect?

CVE-2021-27312 affects gleez cms. Severity is critical (CVSS 9.4). 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.

How urgent is CVE-2021-27312?

Priority 59/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

PHP vulnerabilities

References

← Back to latest CVEs