CVE intelligence and bounded remediation

CVE-2017-2666 — It was discovered in Undertow that the code that parsed the HTTP request line permitted invalid characters

Medium CVSS 6.5

It was discovered in Undertow that the code that parsed the HTTP request line permitted invalid characters. This could be exploited, in conjunction with a proxy that also permitted the invalid characters but with a different interpretation, to inject data into the HTTP response. By manipulating the HTTP response the attacker could poison a web-cache, perform an XSS attack, or obtain sensitive information from requests other than their own.

Severity
Medium
CVSS
6.5 (3.0)
Published
2018-07-27
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-444

Affected products

  • redhat / undertow
  • redhat / jboss_enterprise_application_platform / 7.0.0
  • redhat / jboss_enterprise_application_platform / 7.1.0
  • debian / debian_linux / 9.0
  • debian / debian_linux / 10.0

Showing 5 representative product identities from 7 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

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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