CVEvulnerability

CVE-2020-5247

7.5 HIGH Published 2020-02-28 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2020-02-28
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L
CVSS 3.1 ([email protected])
7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 2.0 ([email protected])
5.0 MEDIUM — AV:N/AC:L/Au:N/C:N/I:P/A:N
Weaknesses
CWE-113, CWE-74

Description

In Puma (RubyGem) before 4.3.2 and before 3.12.3, if an application using Puma allows untrusted input in a response header, an attacker can use newline characters (i.e. `CR`, `LF` or`/r`, `/n`) to end the header and inject malicious content, such as additional headers or an entirely new response body. This vulnerability is known as HTTP Response Splitting. While not an attack in itself, response splitting is a vector for several other attacks, such as cross-site scripting (XSS). This is related to CVE-2019-16254, which fixed this vulnerability for the WEBrick Ruby web server. This has been fixed in versions 4.3.2 and 3.12.3 by checking all headers for line endings and rejecting headers with those characters.

Affected configurations

• puma puma (<= 3.12.3) • puma puma (>= 4.0.0 <= 4.3.2) • ruby-lang ruby (<= 2.3.0) • ruby-lang ruby (>= 2.4.0 <= 2.4.7) • ruby-lang ruby (>= 2.5.0 <= 2.5.6) • ruby-lang ruby (>= 2.6.0 <= 2.6.4) • ruby-lang ruby 2.7.0 • debian debian linux 9.0 • fedoraproject fedora 30 • fedoraproject fedora 31 • fedoraproject fedora 32

Related

Weakness · CWE (2)

  • CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers weakness
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component weakness

References