CVE-2026-20045VulnerabilityPublished 21 Jan 2026Updated 26 Feb 2026

CVE-2026-20045: Cisco Unified Communications Manager · Code Injection

Affects Cisco Unified Communications ManagerSource CVE Database V5

Exploited in the wild · KEV due 11 Feb 2026 · 4% EPSS : apply the vendor's fix or mitigations to Cisco Unified Communications Manager now.

Data as of 26 Oct 2026, 08:30 UTC

CVSS 3.1 base score

8.2High

How severe the flaw is on the 0–10 CVSS scale.

KEV deadline: 11 Feb 2026 US federal agencies must patch by this date; a sensible deadline for everyone else.
EPSS: 4.5% chance of exploitation in 30 days – higher than 91% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: Low
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

t = 0 is the CVE’s publication on cve.org

Disclosed: evidence found.
CVE published 21 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: evidence found.
Listed in CISA KEV the same day as disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

CVE ID reserved
by Cisco Systems, Inc.
8 Oct 202511:59 UTC, 105 days before disclosure
CVE published
on cve.org
21 Jan 202616:26 UTC, t = 0
In Threat Radar
record ingested
21 Jan 202616:35 UTC, 10 minutes after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
21 Jan 2026, the same day as disclosure
KEV remediation due
US federal deadline
11 Feb 2026, 21 days after disclosure

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Affected software

Product	Affected	Fixed in
CiscoCisco Unified Communications Manager	Affected =14 =14SU1 =14SU2 =14SU3 =15 =15SU1 =14SU4 =14SU4a =15SU1a =15SU2 =15.0.1.13010-1 =15.0.1.13011-1 =15.0.1.13012-1 =15.0.1.13013-1 =15.0.1.13014-1 =15.0.1.13015-1 =15.0.1.13016-1 =15.0.1.13017-1 =15SU3a	Fixed in–
CiscoCisco Unified Communications Manager IM and Presence Service	Affected =14 =14SU1 =14SU2 =14SU2a =14SU3 =15 =15SU1 =14SU4 =15SU2 =15SU3	Fixed in–
CiscoCisco Unity Connection	Affected =14 =14SU1 =14SU2 =14SU3 =14SU3a =15 =15SU1 =14SU4 =15SU2 =15SU3	Fixed in–

Check the firmware or software version for Cisco Unified Communications Manager in the device's admin interface against the vendor advisory.

Description

A vulnerability in 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), Cisco Unity Connection, and Cisco Webex Calling Dedicated Instance could allow an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device.  This vulnerability is due to improper validation of user-supplied input in HTTP requests. An attacker could exploit this vulnerability by sending a sequence of crafted HTTP requests to the web-based management interface of an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root.  Note: Cisco has assigned this security advisory a Security Impact Rating (SIR) of Critical rather than High as the score indicates. The reason is that exploitation of this vulnerability could result in an attacker elevating privileges to root.

Impact

The impact of CVE-2026-20045 is severe for organizations relying on Cisco Unified Communications infrastructure. Successful exploitation allows attackers to gain unauthorized root-level control over critical communication servers, potentially leading to interception, manipulation, or disruption of voice and video communications. This could compromise sensitive corporate communications, enable lateral movement within networks, and facilitate further attacks such as data exfiltration or ransomware deployment. The vulnerability affects core telephony and collaboration platforms, which are often integral to business operations, making downtime or compromise highly disruptive. Given the unauthenticated remote attack vector, any exposed management interface significantly increases risk. The broad range of affected versions means many organizations may be vulnerable if patches are not applied promptly. The absence of known exploits in the wild currently reduces immediate risk but does not diminish the urgency for mitigation due to the critical nature of the flaw.

Mitigation

To mitigate CVE-2026-20045, organizations should immediately identify all affected Cisco Unified Communications products and versions within their environment. Applying the latest security patches or software updates from Cisco as soon as they become available is paramount. Until patches are deployed, restrict access to the web-based management interfaces by implementing network segmentation and firewall rules to limit exposure to trusted administrative networks only. Employ strong authentication and multi-factor authentication (MFA) for management access where possible. Monitor network traffic and logs for unusual HTTP requests or signs of exploitation attempts targeting the management interface. Disable or remove any unnecessary services or interfaces that could be exploited. Additionally, conduct regular vulnerability scans and penetration tests focused on Unified Communications infrastructure to detect potential weaknesses. Maintain an incident response plan tailored to Unified Communications compromise scenarios. Finally, stay informed through Cisco security advisories and threat intelligence feeds for updates or emerging exploit activity.

CWE-94Improper Control of Generation of Code ('Code Injection') (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #10OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.
Architecture and Design · Refactoring
Refactor your program so that you do not have to dynamically generate code.
Architecture and Design
Run your code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
OWASP Cheat Sheets
Server Side Request Forgery Prevention (opens in a new tab)
Unvalidated Redirects and Forwards (opens in a new tab)
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V5.2.8 (opens in a new tab)
V5.2.5 (opens in a new tab)
V1.5.1 (opens in a new tab)
Attack patterns
Leverage Executable Code in Non-Executable Files (opens in a new tab)
Manipulating User-Controlled Variables (opens in a new tab)
Code Injection (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

Timeline

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Feb 2026, 15:26 UTC

WeaknessesCWE-94

Technical details

References

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