Red HatCVE-2026-103399
Red Hat Enterprise Linux: request smuggling
Medium5.3CVE-2026-103399 · Published Sep 30, 2026
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.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10 Product | all versions | No fix yet |
| Red Hat Enterprise Linux 6 Product | all versions | No fix yet |
| Red Hat Enterprise Linux 7 Product | all versions | No fix yet |
| Red Hat Enterprise Linux 8 Product | all versions | No fix yet |
| Red Hat Enterprise Linux 9 Product | all versions | No fix yet |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-444
More Red Hat advisories
All Red Hat| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 30 | Assisted Installer for Red Hat OpenShift Container Platform : path traversal | High7.3 | No fix yet |
| Sep 30 | A trust-boundary flaw in CRI-O's sandbox state persistence | High7.8 | No fix yet |
| Sep 30 | Red Hat rpm. RPMTAG_FILESIGNATURES: heap buffer overflow | High7.1 | No fix yet |
| Sep 29 | Red Hat libsoup.: buffer overflow | High8.6 | No fix yet |
| Sep 29 | Red Hat libsoup.: buffer overflow | High8.6 | No fix yet |
| Sep 29 | Red Hat libsoup.: buffer overflow | High8.6 | No fix yet |