CVE-2026-1760
📋 TL;DR
This HTTP request smuggling vulnerability in SoupServer allows remote attackers to send specially crafted requests that bypass normal request processing. Unauthenticated clients can exploit this to smuggle additional requests over persistent connections, potentially causing denial-of-service or unintended request processing. Any system running vulnerable versions of SoupServer with HTTP/1.1 support is affected.
💻 Affected Systems
- SoupServer
⚠️ Risk & Real-World Impact
Worst Case
Complete server takeover through request smuggling leading to authentication bypass, data exfiltration, or persistent DoS conditions that require server restart.
Likely Case
Denial-of-service conditions causing service disruption, potential cache poisoning, or unintended request processing that could lead to information disclosure.
If Mitigated
Limited impact with proper network segmentation, request validation, and monitoring in place to detect anomalous request patterns.
🎯 Exploit Status
Exploitation requires understanding of HTTP request smuggling techniques and ability to craft malformed Transfer-Encoding headers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific version
Vendor Advisory: https://access.redhat.com/security/cve/CVE-2026-1760
Restart Required: Yes
Instructions:
1. Check current SoupServer version. 2. Apply vendor-provided patch or update to fixed version. 3. Restart SoupServer service. 4. Verify fix is applied.
🔧 Temporary Workarounds
Disable HTTP keep-alive
linuxPrevents persistent connections that are required for this exploit
# Add to SoupServer configuration: keep-alive-timeout=0
Use reverse proxy with request validation
allDeploy a reverse proxy that validates and sanitizes HTTP requests before forwarding to SoupServer
🧯 If You Can't Patch
- Implement network segmentation to isolate SoupServer from untrusted networks
- Deploy WAF with HTTP request smuggling protection rules
🔍 How to Verify
Check if Vulnerable:
Check SoupServer version against vendor advisory. Test with crafted HTTP requests containing Transfer-Encoding: chunked and Connection: keep-alive headers.Check Version:
soupserver --version or check package manager (rpm -q soupserver, dpkg -l soupserver)Verify Fix Applied:
Verify SoupServer version is updated to patched version. Test with same crafted requests to ensure proper connection closure.📡 Detection & Monitoring
Log Indicators:
- Multiple requests from single connection with abnormal timing
- Requests with malformed Transfer-Encoding headers
- Connection persistence beyond configured timeout
Network Indicators:
- HTTP requests with Transfer-Encoding: chunked and Connection: keep-alive headers
- Abnormal request/response timing patterns
- Requests that don't properly terminate
SIEM Query:
source="soupserver" AND (http_header="Transfer-Encoding: chunked" AND http_header="Connection: keep-alive")