CVE-2023-1721: Yoga Class Registration System version 1.0 allows an administrator to execute commands on the server

This month

CRITICAL 9.1DOWNGRADE

CVE-2023-1721 is a critical-severity flaw (CVSS 9.1) affecting yoga class registration system. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Yoga Class Registration System version 1.0 allows an administrator to execute commands on the server. This is possible because the application does not correctly validate the thumbnails of the classes uploaded by the administrators.

Why this priority

Critical severity
Public exploit reference

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

Risk facts

CVSS score	9.1 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	High
User interaction	None
EPSS exploit chance	1.0% (top 38%)
CISA exploited list	No
Weakness	CWE-434
Published	2023-06-24
Last modified	2026-06-17

Publisher (CNA): Fluid Attacks · Vendor: yoga class registration system project

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

Am I affected?

Timeline

2023-06-24 00:15 UTCPublished CVE record published
2026-06-17 05:28 UTCUpdated Record last modified

yoga class registration system project yoga class registration system DOWNGRADE

Affected: 1.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 1.0

1. Check installed version

apt-cache policy yoga-class-registration-system || rpm -q yoga-class-registration-system || yoga-class-registration-system --version

2. No fixed release: DOWNGRADE to a release before 1.0 (Debian / Ubuntu)

apt-cache madison yoga-class-registration-system sudo apt install yoga-class-registration-system=<VERSION_BEFORE_1.0> sudo apt-mark hold yoga-class-registration-system

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

dnf --showduplicates list yoga-class-registration-system sudo dnf downgrade yoga-class-registration-system-<VERSION_BEFORE_1.0> sudo dnf versionlock add yoga-class-registration-system

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-2023-1721?

yoga class registration system: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2023-1721 being exploited?

CVE-2023-1721 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-2023-1721 affect?

CVE-2023-1721 affects yoga class registration system. Severity is critical (CVSS 9.1). Yoga Class Registration System version 1.0 allows an administrator to execute commands on the server. This is possible because the application does not correctly validate the thumbnails of the classes uploaded by the administrators.

How urgent is CVE-2023-1721?

Priority 52/100. Critical severity; Public exploit reference

Related CVEs

CVE-2024-7914 LOW 3.5 DOWNGRADE A vulnerability classified as problematic has been found in SourceCodester Yoga Class Registration System 1.0
CVE-2024-7853 MEDIUM 6.3 DOWNGRADE A vulnerability was found in SourceCodester Yoga Class Registration System up to 1.0
CVE-2024-7852 LOW 3.5 DOWNGRADE A vulnerability was found in SourceCodester Yoga Class Registration System 1.0 and classified as problematic
CVE-2024-7851 MEDIUM 6.3 DOWNGRADE A vulnerability has been found in SourceCodester Yoga Class Registration System 1.0 and classified as critical
CVE-2023-29626 HIGH 7.5 DOWNGRADE Yoga Class Registration System 1.0 was discovered to contain a SQL injection vulnerability via the cid paramet

References

← Back to latest CVEs