How severe is CVE-2021-39296?

CVE-2021-39296 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-39296 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39296?

CVE-2021-39296 affects Openbmc-project Openbmc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-39296?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-39296 published?

CVE-2021-39296 was published on 2021-09-09 and last updated on 2026-06-17.

CVE-2021-39296

CVE-2021-39296 is a critical-severity vulnerability in Openbmc-project Openbmc with a CVSS 3.x base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
CVSS v2: 10.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Openbmc-project Openbmc
Published: 2021-09-09
Last modified: 2026-06-17

Description

In OpenBMC 2.9, crafted IPMI messages allow an attacker to bypass authentication and gain full control of the system.

Frequently asked questions

What is CVE-2021-39296?: In OpenBMC 2.9, crafted IPMI messages allow an attacker to bypass authentication and gain full control of the system.
How severe is CVE-2021-39296?: CVE-2021-39296 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-39296 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39296?: CVE-2021-39296 affects Openbmc-project Openbmc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-39296?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-39296 published?: CVE-2021-39296 was published on 2021-09-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:openbmc-project:openbmc:2.9.0:-:*:*:*:*:*:*

More vulnerabilities in Openbmc-project Openbmc

CVE-2020-14156 — High (CVSS 8.8): user_channel/passwd_mgr.cpp in OpenBMC phosphor-host-ipmid before 2020-04-03 does not ensure that /etc/ipmi-pass has…
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CVE-2022-2809 — High (CVSS 8.2): A vulnerability in bmcweb of OpenBMC Project allows user to cause denial of service. When fuzzing the multipart_parser…
CVE-2021-39295 — High (CVSS 7.5): In OpenBMC 2.9, crafted IPMI messages allow an attacker to cause a denial of service to the BMC via the netipmid (IPMI…
CVE-2022-35729 — High (CVSS 7.5): Out of bounds read in firmware for OpenBMC in some Intel(R) platforms before version 0.72 may allow unauthenticated…

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Other CWE-287 (Improper Authentication) vulnerabilities

CVE-2026-45480 — Critical (CVSS 10.0): Improper authentication in Azure Active Directory allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-46389 — Critical (CVSS 10.0): UDS Identity Config builds the Keycloak configuration image (realm, plugins, theme, truststore, JARs) consumed by UDS…
CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

Browse all CWE-287 (Improper Authentication) vulnerabilities →