This is a summary of the AI-generated 10-question deep analysis. The full version (longer answers, follow-up Q&A, related CVEs) requires login. Read the full analysis β
Q1What is this vulnerability? (Essence + Consequences)
π¨ **Essence**: Yaws Web Server (v1.91) has a critical **HTTP Directory Traversal** flaw. π **Consequences**: Attackers can read sensitive files, specifically the **SSL Private Key**, leading to total server compromise.
Q2Root Cause? (CWE/Flaw)
π‘οΈ **Root Cause**: **Unauthenticated Local File Inclusion (LFI)**. The server fails to sanitize input paths, allowing `../` sequences to escape the web root. π **Flaw**: Poor path validation in the request handler.
Q3Who is affected? (Versions/Components)
π¦ **Affected**: **Yaws** (Yet Another Web Server) based on Erlang. π **Version**: Specifically **v1.91**. π **Mode**: Both standalone and embedded execution modes are at risk.
Q4What can hackers do? (Privileges/Data)
π» **Hackers Can**: Read arbitrary files on the server. π **Key Data**: Access the **SSL Private Key**. π΅οΈ **Impact**: Decrypt HTTPS traffic, impersonate the server, and gain deeper system access.
Q5Is exploitation threshold high? (Auth/Config)
β‘ **Threshold**: **LOW**. π **Auth**: **Unauthenticated**. No login required. π **Config**: Exploitable via standard HTTP requests on port 8080. Easy to trigger remotely.
Q6Is there a public Exp? (PoC/Wild Exploitation)
π **Public Exp?**: **YES**. π **PoC**: Available on Exploit-DB (ID: 42303) and ProjectDiscovery Nuclei templates. π **Wild Exploitation**: High risk due to simple `/%5C../` payload.
Q7How to self-check? (Features/Scanning)
π **Self-Check**: Scan for Yaws server banners. π§ͺ **Test**: Send `GET /%5C../` to port 8080. π **Result**: If server responds with file content (not 404), it is vulnerable.
Q8Is it fixed officially? (Patch/Mitigation)
π οΈ **Official Fix**: The data implies a fix exists for versions > 1.91. π₯ **Action**: Upgrade Yaws to the latest stable version. π **Mitigation**: Apply vendor patches immediately upon release.
Q9What if no patch? (Workaround)
π§ **No Patch?**: Block external access to port 8080. π« **WAF**: Configure rules to block `../` or `%5C../` in URL paths. π **Restrict**: Limit file access permissions on the server OS.
Q10Is it urgent? (Priority Suggestion)
π₯ **Urgency**: **CRITICAL**. π¨ **Priority**: **P1**. Since it is unauthenticated and exposes SSL keys, immediate patching or mitigation is required to prevent data breach.