CVE-2021-3801

mediumpriority · track · 26EPSS 0.010 · 64 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.04% (64th) EPSS

CVSS 4.3 · medium

Is it mine?

3 products

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-24

prism is vulnerable to Inefficient Regular Expression Complexity

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.3–7.5

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · security@huntr.devexploitability 3.9 · impact 3.6

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · OSV

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Vendor and ecosystem advisories describing this.

GHSA-hqhp-5p83-hx96prismjs Regular Expression Denial of Service vulnerability2021-09-20ghsa · osvUS
Prism is a syntax highlighting library. The prismjs package is vulnerable to ReDoS (regular expression denial of service). An attacker that is able to provide a crafted HTML comment as input may cause an application to consume an excessive amount of CPU.

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-09-15modified 2026-06-17

External citations — patches, advisories, analysis.

scry

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