CVE-2021-34701 | Cisco Unified Communications Products Path Traversal Vulnerability

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), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), and Cisco Unity Connection could allow an authenticated, remote attacker to access sensitive data on an affected device. This vulnerability exists because the web-based management interface does not properly validate user-supplied input. An attacker could exploit this vulnerability by sending a crafted HTTP request that contains directory traversal character sequences to an affected system. A successful exploit could allow the attacker to access sensitive files on the affected system.

Published: 2021-11-04 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-34701 is rated Low Risk (27.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.08%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-34701

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2023-03-07 1.05% 0.08% -0.98%
2 2022-04-01 5.46% 1.05% -4.41%
3 2022-02-04 5.46%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-34701

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 1.4 [email protected]
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 1.4 [email protected]
4.0 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
8.0 2.9 [email protected]

Weakness enumeration for CVE-2021-34701

Affected software / configurations for CVE-2021-34701

Vendor Product Version Raw CPE
cisco unified_communications_manager < 14su1 cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:*:*:*:*
cisco unified_communications_manager < 14su1 cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:session_management:*:*:*
cisco unified_communications_manager_im_and_presence_service < 14su1 cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:*:*:*:*:*:*:*:*
cisco unity_connection < 14su1 cpe:2.3:a:cisco:unity_connection:*:*:*:*:*:*:*:*

References for CVE-2021-34701

cvelogic Threat Intelligence