How severe is CVE-2021-34736?

CVE-2021-34736 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-34736 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34736?

CVE-2021-34736 affects Cisco Unified Computing System. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34736?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-34736 published?

CVE-2021-34736 was published on 2021-10-21 and last updated on 2026-06-17.

CVE-2021-34736

CVE-2021-34736 is a medium-severity vulnerability in Cisco Unified Computing System with a CVSS 3.x base score of 5.3. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Unified Computing System
Published: 2021-10-21
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Software could allow an unauthenticated, remote attacker to cause the web-based management interface to unexpectedly restart. The vulnerability is due to insufficient input validation on the web-based management interface. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to cause the interface to restart, resulting in a denial of service (DoS) condition.

Frequently asked questions

What is CVE-2021-34736?: A vulnerability in the web-based management interface of Cisco Integrated Management Controller (IMC) Software could allow an unauthenticated, remote attacker to cause the web-based management interface to unexpectedly restart. The vulnerability is due to insufficient input validation on the web-based management interface. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to cause the interface to restart, resulting in a denial of service (DoS) condition.
How severe is CVE-2021-34736?: CVE-2021-34736 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-34736 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34736?: CVE-2021-34736 affects Cisco Unified Computing System. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34736?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34736 published?: CVE-2021-34736 was published on 2021-10-21 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-imc-gui-dos-TZjrFyZh

Affected products (1)

cpe:2.3:a:cisco:unified_computing_system:*:*:*:*:*:*:*:*

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