CVE intelligence and bounded remediation
CVE-2023-40167 — Jetty is a Java based web server and servlet engine
Jetty is a Java based web server and servlet engine. Prior to versions 9.4.52, 10.0.16, 11.0.16, and 12.0.1, Jetty accepts the `+` character proceeding the content-length value in a HTTP/1 header field. This is more permissive than allowed by the RFC and other servers routinely reject such requests with 400 responses. There is no known exploit scenario, but it is conceivable that request smuggling could result if jetty is used in combination with a server that does not close the connection after sending such a 400 response. Versions 9.4.52, 10.0.16, 11.0.16, and 12.0.1 contain a patch for this issue. There is no workaround as there is no known exploit scenario.
- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Published
- 2023-09-15
- CISA KEV
- Not currently listed
- Ecosystem
- java/maven
- Weaknesses
- CWE-130
Affected products
- eclipse / jetty
- eclipse / jetty / 12.0.0
- debian / debian_linux / 10.0
- debian / debian_linux / 11.0
- debian / debian_linux / 12.0
Matched remediation archetype
HTTP request smuggling and message-boundary ambiguity
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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
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