CVE-2017-1002201

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2019-10-15 · updated 2026-06-17
Weakness: CWE-79

Description

In haml versions prior to version 5.0.0.beta.2, when using user input to perform tasks on the server, characters like < > " ' must be escaped properly. In this case, the ' character was missed. An attacker can manipulate the input to introduce additional attributes, potentially executing code.

Affected products

Debian Linux: 8.0, 9.0
Haml: before 5.0.0 — fixed in 5.0.0

How to fix

Upgrade to a fixed version: Haml 5.0.0. Check the vendor advisory for mitigations.

References

https://github.com/haml/haml/commit/18576ae6e9bdcb4303fdbe6b3199869d289d67c2
https://lists.debian.org/debian-lts-announce/2019/11/msg00007.html
https://lists.debian.org/debian-lts-announce/2021/12/msg00028.html
https://security.gentoo.org/glsa/202007-27
https://snyk.io/vuln/SNYK-RUBY-HAML-20362
https://github.com/haml/haml/commit/18576ae6e9bdcb4303fdbe6b3199869d289d67c2
https://lists.debian.org/debian-lts-announce/2019/11/msg00007.html
https://lists.debian.org/debian-lts-announce/2021/12/msg00028.html
https://security.gentoo.org/glsa/202007-27
https://snyk.io/vuln/SNYK-RUBY-HAML-20362

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