CVE-2026-3634: Libsoup: libsoup: http header injection and response splitting via crlf injection in content-type header
CSIRTS triage
- What
- libsoup fails to properly sanitize HTTP headers, allowing CRLF injection in the Content-Type header leading to response splitting.
- Who is affected
- Applications using libsoup for HTTP client functionality.
- Urgency
- Low priority with CVSS 3.9; requires specific header injection exploitation.
- Action
- Update libsoup to a version with proper HTTP header sanitization.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-3634
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-36340.18% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 8% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-3634 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
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