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HTTP Multiline Header Termination

High severity GitHub Reviewed Published Apr 24, 2023 in laminas/laminas-diactoros • Updated Nov 4, 2023

Package

composer laminas/laminas-diactoros (Composer)

Affected versions

< 2.18.1
= 2.19.0
= 2.20.0
= 2.21.0
= 2.22.0
= 2.23.0
>= 2.24.0, < 2.24.2
>= 2.25.0, < 2.25.2

Patched versions

2.18.1
2.19.1
2.20.1
2.21.1
2.22.1
2.23.1
2.24.2
2.25.2

Description

Impact

Affected versions of Laminas Diactoros accepted a single line feed (LF / \n ) character at the end of a header name. When serializing such a header name containing a line-feed into the on-the-wire representation of a HTTP/1.x message, the resulting message would be syntactically invalid, due to the header line being terminated too early. An attacker that is able to control the header names that are passed to Laminas Diactoros would be able to intentionally craft invalid messages, possibly causing application errors or invalid HTTP requests being sent out with an PSR-18 HTTP client. The latter might present a denial of service vector if a remote service’s web application firewall bans the application due to the receipt of malformed requests.

Patches

The problem has been patched in the following versions:

  • 2.18.1
  • 2.19.1
  • 2.20.1
  • 2.21.1
  • 2.22.1
  • 2.23.1
  • 2.24.2
  • 2.25.2

Workarounds

Validate HTTP header keys and/or values, and if using user-supplied values, filter them to strip off leading or trailing newline characters before calling withHeader().

References

References

@weierophinney weierophinney published to laminas/laminas-diactoros Apr 24, 2023
Published by the National Vulnerability Database Apr 24, 2023
Published to the GitHub Advisory Database Apr 24, 2023
Reviewed Apr 24, 2023
Last updated Nov 4, 2023

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS score

0.070%
(32nd percentile)

Weaknesses

CVE ID

CVE-2023-29530

GHSA ID

GHSA-xv3h-4844-9h36

Source code

Credits

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