How severe is CVE-2026-20045?

CVE-2026-20045 has a CVSS score of 8.2/10, rated HIGH. Immediate patching is strongly recommended.

Which products are affected by CVE-2026-20045?

Affected package information for CVE-2026-20045 is not yet fully mapped. Check the official advisory links for details.

How do I patch CVE-2026-20045?

Apply the cisco unified communications manager security patch or hotfix for CVE-2026-20045 on the affected version, following the vendor advisory for your exact build.

How do I detect CVE-2026-20045 across my infrastructure?

Inventory every cisco unified communications manager deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

How do I mitigate CVE-2026-20045 if there is no patch (or I can't update yet)?

Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

How does O3 Security protect against CVE-2026-20045?

O3 detects and blocks CVE-2026-20045 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Is CVE-2026-20045 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-20045 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-20045?

CVE-2026-20045 has an EPSS (Exploit Prediction Scoring System) score of 4.3%, placing it in the 90th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

Is CVE-2026-20045 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2026-20045 (Cisco Unified Communications Products Code Injection Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2026-01-21. CISA required all US federal civilian agencies to remediate this vulnerability by 2026-02-11. The required action was: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2026-20045?

CVE-2026-20045 is classified as Code Injection (CWE-94). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

Which products and versions are affected by CVE-2026-20045?

CVE-2026-20045 affects cisco unified communications manager; cisco unified communications manager im and presence service; cisco unity connection. Check the affected-products list on this page against your deployed version to confirm exposure.

When was CVE-2026-20045 published, and has it been updated?

CVE-2026-20045 was published on January 21, 2026 and was last updated on June 17, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2026-20045: Unified Communications Manager Code Injection…

EPSS Exploitation Probability

via FIRST.org ↗

4.3%probability of exploitation in next 30 days

Lower Risk90th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

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.

Affected Products

3 products · 8 configurations

Application

unified communications managercisco

≥ 15.0 && ≤ 15su3a

range

Application

unified communications manager im and presence servicecisco

≥ 15.0 && ≤ 15su3a

range

Application

unity connectioncisco

≥ 15.0 && ≤ 15su3

range

Detection & mitigation playbook

Vendor / appliance

Detect
Inventory every cisco unified communications manager deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the cisco unified communications manager security patch or hotfix for CVE-2026-20045 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-20045 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2026-20045. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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 se

O3 Security · Runtime Protection

Is CVE-2026-20045 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-20045 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.

Protect my workloads How runtime protection works

CVE-2026-20045

EPSS Exploitation Probability

Description

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

How O3 protects you

Frequently Asked Questions

Is CVE-2026-20045 being exploited in your environment?