Request smuggling via conflicting Content-Length headers
Published Apr 23, 2026 · Updated Apr 23, 2026
HTTP request smuggling in libsoup packages for Red Hat Enterprise Linux allows remote attackers to desynchronize HTTP message boundaries. soup_message_headers_append_common() appends repeated Content-Length values without rejecting duplicates whose lengths conflict. Exploitation requires attacker-controlled HTTP/1 traffic and another HTTP parser that resolves the conflicting lengths differently, allowing a request to cross message boundaries.
Summary
What happened
HTTP request smuggling in libsoup packages for Red Hat Enterprise Linux allows remote attackers to desynchronize HTTP message boundaries. soup_message_headers_append_common() appends repeated Content-Length values without rejecting duplicates whose lengths conflict. Exploitation requires attacker-controlled HTTP/1 traffic and another HTTP parser that resolves the conflicting lengths differently, allowing a request to cross message boundaries.
The record
- CVE
- CVE-2026-2708
- Published
- Apr 23, 2026
- Updated
- Apr 23, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Enterprise Linux 6
- Classifications
- CWE-444, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 23, 2026CVE publishedPublication date reported by the CVE source.
- Apr 23, 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?
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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