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## https://sploitus.com/exploit?id=557D09CF-0158-5145-8B1C-878B3F3B6E09
# π¨ CVE-2026-20045 β Critical Cisco Unified Communications Zero-Day
> A critical vulnerability in **:contentReference[oaicite:0]{index=0}** Unified Communications products that allows remote attackers to execute commands without authentication.
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## π Table of Contents
- **Overview**
- **Technical Details**
- **Severity**
- **Affected Products & Versions**
- **Exploit Status**
- **Potential Impact**
- **Detection**
- **Remediation**
- **Mitigation**
- **Summary**
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## π Overview
**CVE-2026-20045** 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.
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## π§ Technical Details
- 𧩠**Type:** Remote Code Execution / Code Injection
- π **Cause:** Improper validation of user-supplied HTTP request input
- π₯ **Attack Vector:** Attacker sends specially crafted HTTP requests to the management interface
- πͺ **Privileges Required:** None
These flaws allow the attacker not only to run arbitrary commands at user level but also *escalate privileges to root* once initial access is gained.
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## π Severity
| Metric | Value |
|--------|--------|
| **CVSS Score (v3.1)** | **8.2 (High)** |
| **Attack Vector** | Network |
| **Privileges Required** | None |
| **User Interaction** | None |
| **Confidentiality Impact** | High |
| **Integrity Impact** | Low |
| **Availability Impact** | None |
| **Exploited in the Wild** | Yes (CISA KEV) |
Because this RCE leads to full system compromise, Cisco classifies it with a **Critical Security Impact Rating** even though the raw CVSS score is 8.2.
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## π¦ Affected Products & Versions
The following Cisco products are affected:
- **Cisco Unified Communications Manager (Unified CM)**
- **Unified CM Session Management Edition (SME)**
- **Unified CM IM & Presence Service (IM&P)**
- **Cisco Unity Connection**
- **Cisco Webex Calling Dedicated Instance**
Older releases like **12.5** may require *migration* rather than a patch; newer branches (14.x, 15.x) have patches available or service updates to fix the issue.
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## π₯ Exploit Status
- π§ͺ **Zero-day reported:** January 21, 2026
- π **Actively exploited in the wild:** Yes
- π **Added to CISA Known Exploited Vulnerabilities (KEV) catalog**
Federal agencies were required to patch or mitigate by **February 11, 2026** due to confirmed real-world exploitation.
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## π₯ Potential Impact
If successfully exploited, attackers can:
- π¨ Execute arbitrary OS commands
- π Obtain user-level access
- π Escalate privileges to root
- π‘ Install malware or backdoors
- π Disrupt voice, messaging, and presence services
Because Unified Communications infrastructure is mission-critical in many enterprises, compromise can have wide operational impact.
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## π Detection Tips
Watch for:
- Unusual or malformed HTTP requests targeting management interfaces
- Unexpected logins or shell activity on Unified Communication appliances
- Network scanning or reconnaissance on ports hosting web-based admin interfaces
Use logging and intrusion detection tools to monitor web components.
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## π Remediation
### β
Apply Official Patches
Cisco has released official security updates for the affected products. Update to the latest fixed versions recommended by Ciscoβs security advisories.
### π Verify
- Confirm patches installed on all UC appliances
- Reboot devices after patching
- Validate no obsolete or unsupported versions remain
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## 𧱠Temporary Mitigation
If immediate patching isnβt possible:
- Restrict web management interfaces behind firewalls
- Restrict access to trusted IP ranges only
- Segment management traffic from general network access
These steps reduce external exposure even if they donβt remove the underlying flaw.
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## π§Ύ Summary
| Field | Description |
|-------|-------------|
| **CVE ID** | CVE-2026-20045 |
| **Nickname** | Cisco Unified Communications RCE |
| **Type** | Remote Command Execution |
| **Severity** | High / Critical Impact |
| **Authentication Required** | No |
| **Exploit Status** | Actively exploited |
| **Remediation** | Patches available β update immediately |
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## β οΈ Final Advisory
This vulnerability allows **unauthenticated remote attackers** to inject and run arbitrary commands, elevate privileges, and potentially take full control of Cisco Unified Communications infrastructure.
**Apply vendor patches without delay** and isolate management interfaces to minimize risk.