How severe is CVE-2021-23341?

CVE-2021-23341 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-23341 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23341?

CVE-2021-23341 affects Prismjs Prism. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23341?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-23341 published?

CVE-2021-23341 was published on 2021-02-18 and last updated on 2026-06-17.

CVE-2021-23341

CVE-2021-23341 is a high-severity vulnerability in Prismjs Prism with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Prismjs Prism
Published: 2021-02-18
Last modified: 2026-06-17

Description

The package prismjs before 1.23.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via the prism-asciidoc, prism-rest, prism-tap and prism-eiffel components.

Frequently asked questions

What is CVE-2021-23341?: The package prismjs before 1.23.0 are vulnerable to Regular Expression Denial of Service (ReDoS) via the prism-asciidoc, prism-rest, prism-tap and prism-eiffel components.
How severe is CVE-2021-23341?: CVE-2021-23341 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-23341 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23341?: CVE-2021-23341 affects Prismjs Prism. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23341?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-23341 published?: CVE-2021-23341 was published on 2021-02-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:prismjs:prism:*:*:*:*:*:node.js:*:*

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