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How CVE-2025-20255 Works
The vulnerability in Cisco Webex Meetings’ client join services stems from improper validation of HTTP requests, allowing an attacker to poison cached responses. By sending specially crafted HTTP requests, an attacker can manipulate stored responses in the cache. When legitimate users attempt to join a meeting, the service may return these poisoned responses instead of legitimate ones. This HTTP cache poisoning can lead to redirection to malicious servers, session hijacking, or denial of service. The attack exploits flaws in request handling and caching mechanisms, requiring no authentication.
DailyCVE Form
Platform: Cisco Webex Meetings
Version: Pre-42.11.7
Vulnerability: HTTP cache poisoning
Severity: Critical
Date: 07/15/2025
Prediction: Patch by 09/2025
What Undercode Say
curl -X GET "https://webex.com/join" -H "X-Malicious-Header: Poisoned"
import requests
response = requests.get("https://webex.com/join", headers={"X-Cache-Poison": "1"})
How Exploit
- Send malicious HTTP requests
- Manipulate cached responses
- Trigger poisoned cache retrieval
Protection from this CVE
- Update to 42.11.7+
- Disable vulnerable caching
- Implement request validation
Impact
- Session hijacking
- Phishing redirections
- Service disruption
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
