HTTP request smuggling via unsanitized Host header
Published Mar 17, 2026 · Updated Mar 17, 2026
HTTP request smuggling in libsoup on Red Hat Enterprise Linux 7 through 10 allows attackers to inject requests via crafted hostnames. soup_message_set_request_host_from_uri() copies the GUri host value directly into the Host header without rejecting CR or LF characters. Reachability requires an application to process an attacker-controlled URL; a smuggled request can become SSRF in server-side document conversion.
Summary
What happened
HTTP request smuggling in libsoup on Red Hat Enterprise Linux 7 through 10 allows attackers to inject requests via crafted hostnames. soup_message_set_request_host_from_uri() copies the GUri host value directly into the Host header without rejecting CR or LF characters. Reachability requires an application to process an attacker-controlled URL; a smuggled request can become SSRF in server-side document conversion.
The record
- CVE
- CVE-2026-3632
- Published
- Mar 17, 2026
- Updated
- Mar 17, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Enterprise Linux 10
- Classifications
- CWE-1286, T1203
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 17, 2026CVE publishedPublication date reported by the CVE source.
- Mar 17, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Crafted GIO hostname request-injection reproductionproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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