CVE-2021-47701: OpenBMCS 2.4 allows an attacker to escalate privileges from a read user to an admin user by manipulating permi

This month

HIGH 8.8DOWNGRADE

CVE-2021-47701 is a high-severity flaw (CVSS 8.8) affecting openbmcs. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

OpenBMCS 2.4 allows an attacker to escalate privileges from a read user to an admin user by manipulating permissions and exploiting a vulnerability in the update_user_permissions.php script. Attackers can submit a malicious HTTP POST request to PHP scripts in '/plugins/useradmin/' directory.

Why this priority

High severity
Public exploit reference

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

Risk facts

CVSS score	8.8 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	Low
User interaction	None
EPSS exploit chance	0.5% (top 59%)
CISA exploited list	No
Weakness	CWE-862
Published	2025-12-09
Last modified	2026-06-17

Publisher (CNA): VulnCheck · Vendor: openbmcs

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

Am I affected?

Timeline

2025-12-09 21:15 UTCPublished CVE record published
2026-06-17 04:18 UTCUpdated Record last modified

openbmcs openbmcs DOWNGRADE

Affected: 2.4

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.4

1. Check installed version

apt-cache policy openbmcs || rpm -q openbmcs || openbmcs --version

2. No fixed release: DOWNGRADE to a release before 2.4 (Debian / Ubuntu)

apt-cache madison openbmcs sudo apt install openbmcs=<VERSION_BEFORE_2.4> sudo apt-mark hold openbmcs

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

dnf --showduplicates list openbmcs sudo dnf downgrade openbmcs-<VERSION_BEFORE_2.4> sudo dnf versionlock add openbmcs

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-2021-47701?

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

Is CVE-2021-47701 being exploited?

CVE-2021-47701 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-2021-47701 affect?

CVE-2021-47701 affects openbmcs. Severity is high (CVSS 8.8). OpenBMCS 2.4 allows an attacker to escalate privileges from a read user to an admin user by manipulating permissions and exploiting a vulnerability in the update_user_permissions.php script. Attackers can submit a malicious HTTP POST reque

How urgent is CVE-2021-47701?

Priority 46/100. High severity; Public exploit reference

Software pages

PHP vulnerabilities

Related CVEs

CVE-2021-47718 HIGH 7.5 DOWNGRADE OpenBMCS 2.4 contains an information disclosure vulnerability that allows unauthenticated attackers to access
CVE-2021-47704 MEDIUM 6.5 DOWNGRADE OpenBMCS 2.4 contains an SQL injection vulnerability that allows authenticated attackers to manipulate databas
CVE-2021-47703 HIGH 7.2 DOWNGRADE OpenBMCS 2.4 contains an unauthenticated SSRF vulnerability that allows attackers to bypass firewalls and init
CVE-2021-47702 MEDIUM 4.3 DOWNGRADE OpenBMCS 2.4 contains a CSRF vulnerability that allows attackers to perform actions with administrative privil

References

← Back to latest CVEs