The web server must disable HTTP/1.x downgrading.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-264363SRG-APP-000439-WSR-000193SV-264363r984434_ruleCCI-002418medium
Description
HTTP/2 is backward compatible with HTTP/1.x, so it is possible to configure the architecture to implement a front-end server for HTTP/2 while communicating with one or more back-end servers that support only HTTP/1.x. Thus, the front end effectively has to translate or downgrade the requests it receives into the less secure protocol. HTTP downgrading negates the benefits of HTTP/2. If HTTP downgrading cannot be avoided, validate the rewritten/downgraded request against the HTTP/1.1 specification. For example, reject requests that contain newlines in the headers, colons in header names, and spaces in the request method.
STIGDate
Web Server Security Requirements Guide2025-02-12

Related Frameworks

3 paths across 3 frameworks
NIST 800-531 mapping
SC-8
1.00
  • DISA · 4 · disa_xccdf · related
  • DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1711 mapping
3.13.8
1.00
  • DISA · 4 · disa_xccdf · related
  • DISA · 2025-01-23 · disa_cci_list · equivalent
  • NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
CCI1 mapping
CCI-002418
1.00
  • DISA · 4 · disa_xccdf · related

Details

Check Text (C-264363r984434_chk)

If HTTP downgrading is operationally necessary, and the rewritten request is validated against HTTP/1.x specification (i.e., verify requests that contain new lines in the headers, colons in header names, and spaces in the request method are rejected), mark as a CAT III finding. Verify that HTTP/1.x downgrading is disabled. If the HTTP/1.x downgrading is enabled, this is a finding.

Fix Text (F-68184r984433_fix)

Configure the web server to disable HTTP/1.x downgrading. If HTTP downgrading is operationally necessary, validate the rewritten request against the HTTP/1.1 specification, i.e., reject requests that contain new lines in the headers, colons in header names, and spaces in the request method.