How severe is CVE-2021-34773?

CVE-2021-34773 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-34773 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34773?

CVE-2021-34773 primarily affects Cisco Unified Communications Manager. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34773?

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

When was CVE-2021-34773 published?

CVE-2021-34773 was published on 2021-11-04 and last updated on 2026-06-17.

CVE-2021-34773

CVE-2021-34773 is a medium-severity vulnerability in Cisco Unified Communications Manager with a CVSS 3.x base score of 6.5. 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-352.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-352
Affected product: Cisco Unified Communications Manager
Published: 2021-11-04
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P) could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected device. This vulnerability is due to insufficient CSRF protections for the web-based management interface on an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to click a malicious link. A successful exploit could allow the attacker to perform arbitrary actions with the privilege level of the targeted user. These actions could include modifying the device configuration and deleting (but not creating) user accounts.

Frequently asked questions

What is CVE-2021-34773?: A vulnerability in the web-based management interface of Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P) could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected device. This vulnerability is due to insufficient CSRF protections for the web-based management interface on an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to click a malicious link. A successful exploit could allow the attacker to perform arbitrary actions with the privilege level of the targeted user. These actions could include modifying the device configuration and deleting (but not creating) user accounts.
How severe is CVE-2021-34773?: CVE-2021-34773 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-34773 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34773?: CVE-2021-34773 primarily affects Cisco Unified Communications Manager. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34773?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34773 published?: CVE-2021-34773 was published on 2021-11-04 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ucm-csrf-xrTkDu3H

Affected products (6)

cpe:2.3:a:cisco:unified_communications_manager:-:*:*:*:session_management:*:*:*
cpe:2.3:a:cisco:unified_communications_manager:14.0\(1.10000.20\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:10.5\(2\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:11.5\(1\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:12.5:*:*:*:*:*:*:*
cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:14.0:*:*:*:*:*:*:*

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