LibSass up to 3.5.4 Parser eval.cpp Binary_Expression*) resource consumption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in LibSass up to 3.5.4 (Programming Language Software). It has been rated as problematic. Affected by this issue is the function Sass::Eval::operator(Sass::Binary_Expression*) of the file eval.cpp of the component Parser. The manipulation with an unknown input leads to a resource consumption vulnerability. Using CWE to declare the problem leads to CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. Impacted is availability. CVE summarizes:

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.

The bug was discovered 06/02/2018. The weakness was released 12/04/2018 (Website). The advisory is available at This vulnerability is handled as CVE-2018-19837 since 12/03/2018. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

The vulnerability was handled as a non-public zero-day exploit for at least 185 days. During that time the estimated underground price was around $0-$5k.

Upgrading to version 3.5.5 eliminates this vulnerability.






CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
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VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
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Class: Resource consumption
CWE: CWE-400 / CWE-404

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: LibSass 3.5.5


06/02/2018 🔍
12/03/2018 +184 days 🔍
12/04/2018 +1 days 🔍
12/04/2018 +0 days 🔍
12/05/2018 +1 days 🔍
06/12/2023 +1650 days 🔍


Advisory: 210fdff7a65370c2ae24e022a2b35da8c423cc5f
Status: Not defined

CVE: CVE-2018-19837 (🔍)


Created: 12/05/2018 08:14 AM
Updated: 06/12/2023 04:27 PM
Changes: 12/05/2018 08:14 AM (61), 04/17/2020 11:05 AM (1), 06/12/2023 04:27 PM (5)
Complete: 🔍
Cache ID: 44:70E:40


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