What’s Vulnerable › Vulnerabilities

CVE-2018-19837

• Severity: medium (CVSS 6.5 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.8% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2018-12-04 · updated 2026-06-17
• Weakness: CWE-400

Description

In LibSass prior to 3.5.5, Sass::Eval::operator()(Sass::Binary_Expression*) inside eval.cpp allows attackers to cause a denial-of-service resulting from stack consumption via a crafted sass file, because of certain incorrect parsing of '%' as a modulo operator in parser.cpp.

Affected products

• Sass-Lang Libsass: before 3.5.5 — fixed in 3.5.5

How to fix

Upgrade to a fixed version: Sass-Lang Libsass 3.5.5. Check the vendor advisory for mitigations.

References

• http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00047.html
• http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00051.html
• http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00027.html
• https://github.com/sass/libsass/commit/210fdff7a65370c2ae24e022a2b35da8c423cc5f
• https://github.com/sass/libsass/issues/2659
• http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00047.html
• http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00051.html
• http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00027.html
• https://github.com/sass/libsass/commit/210fdff7a65370c2ae24e022a2b35da8c423cc5f
• https://github.com/sass/libsass/issues/2659

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