CVE intelligence and bounded remediation

CVE-2026-2708 — A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic

Medium CVSS 5.3

A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values.

Severity
Medium
CVSS
5.3 (3.1)
Published
2026-04-23
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-444

Affected products

  • gnome / libsoup
  • redhat / enterprise_linux / 6.0
  • redhat / enterprise_linux / 7.0
  • redhat / enterprise_linux / 8.0
  • redhat / enterprise_linux / 9.0
  • redhat / enterprise_linux / 10.0

Matched remediation archetype

HTTP request smuggling and message-boundary ambiguity

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Inventory every proxy, CDN, gateway, load balancer, service mesh, and application server hop on affected request paths.
  • Compare documented parsing and normalization behavior for message length, transfer coding, duplicate headers, and protocol translation.
  • Identify connection reuse and which downstream services trust headers added by intermediaries.

Remediate safely

  • Update affected intermediaries and origin servers and align them on a single standards-compliant request framing policy.
  • Reject ambiguous length, transfer-coding, duplicate, malformed, and unsupported framing before forwarding.
  • Normalize or remove hop-by-hop and identity headers at one controlled boundary and add multi-hop regression tests.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.