VYPR
Medium severity6.5NVD Advisory· Published Mar 2, 2020· Updated Jun 17, 2026

CVE-2020-5249

CVE-2020-5249

Description

In Puma (RubyGem) before 4.3.3 and 3.12.4, if an application using Puma allows untrusted input in an early-hints header, an attacker can use a carriage return character 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-2020-5247, which fixed this vulnerability but only for regular responses. This has been fixed in 4.3.3 and 3.12.4.

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Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
pumaRubyGems
< 3.12.43.12.4
pumaRubyGems
>= 4.0.0, < 4.3.34.3.3

Affected products

12

Patches

Vulnerability mechanics

References

13

News mentions

0

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