CVE-2026-103399

CVE CVE-2026-103399EUVD EUVD-2026-90226Published 2026-09-30T17:42:31.000ZLast changed 2026-09-30T19:11:12.000ZCVSS 5.3

What the advisory describes

A flaw was found in SoupServer (libsoup). When an HTTP/1.x client sends a request with Expect: 100-continue and a request body, and SoupServer returns an early final (non-1xx) response before the body is read, the server neither drains the declared body bytes nor closes the connection. On a keep-alive connection, those leftover bytes are interpreted as a subsequent HTTP request. A remote, unauthenticated attacker can place a complete HTTP request in the body and cause SoupServer to process that smuggled request, leading to unintended request handling.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

• Red Hat — Red Hat Enterprise Linux 10
• Red Hat — Red Hat Enterprise Linux 6
• Red Hat — Red Hat Enterprise Linux 7
• Red Hat — Red Hat Enterprise Linux 8
• Red Hat — Red Hat Enterprise Linux 9

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

• Red Hat — Red Hat Enterprise Linux

Patchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.