How severe is CVE-2018-19839?

CVE-2018-19839 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-19839 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-19839?

CVE-2018-19839 affects Sass-lang Libsass. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-19839?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-19839 published?

CVE-2018-19839 was published on 2018-12-04 and last updated on 2026-06-17.

CVE-2018-19839

CVE-2018-19839 is a medium-severity vulnerability in Sass-lang Libsass with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Sass-lang Libsass
Published: 2018-12-04
Last modified: 2026-06-17

Description

In LibSass prior to 3.5.5, the function handle_error in sass_context.cpp allows attackers to cause a denial-of-service resulting from a heap-based buffer over-read via a crafted sass file.

Frequently asked questions

What is CVE-2018-19839?: In LibSass prior to 3.5.5, the function handle_error in sass_context.cpp allows attackers to cause a denial-of-service resulting from a heap-based buffer over-read via a crafted sass file.
How severe is CVE-2018-19839?: CVE-2018-19839 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-19839 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-19839?: CVE-2018-19839 affects Sass-lang Libsass. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-19839?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-19839 published?: CVE-2018-19839 was published on 2018-12-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sass-lang:libsass:*:*:*:*:*:*:*:*

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