CVE-2021-23341

Regular Expression Denial of Service (ReDoS)

7.5 HighFix available

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

3.17%Up 1.4 points since Apr 14, 2021

What each source reports

CVE List Score used 7.5

Regular Expression Denial of Service (ReDoS)

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.

Record: CVE-2021-23341
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

EUVDEUVD-2021-0662 7.5

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.

Record: EUVD-2021-0662
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-03

GitHub AdvisoriesGHSA-h4hr-7fg3-h35w No score

Denial of service in prismjs

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.

Record: GHSA-h4hr-7fg3-h35w
Weakness: CWE-400
Updated: 2026-11-02

NVD 7.5

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.

Record: CVE-2021-23341
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.0: 5.0 MediumAV:N/AC:L/Au:N/C:N/I:N/A:P
Updated: 2026-11-02

OSV 7.5

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.

Record: CVE-2021-23341
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVDEBIAN-CVE-2021-23341 7.5

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.

Record: DEBIAN-CVE-2021-23341
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

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OSVUBUNTU-CVE-2021-23341 7.5

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.

Record: UBUNTU-CVE-2021-23341
CVSS 3.1: 7.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Updated: 2026-11-02

OSVCLSA-2026-1793304056 No score

TuxCare security update for prismjs (6 CVEs)

TuxCare rebuilt prismjs to address 6 CVEs. Fixed in 1.17.1-tuxcare.1.

Record: CLSA-2026-1793304056
Updated: 2026-11-02

OSVGHSA-h4hr-7fg3-h35w No score

Denial of service in prismjs

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.

Record: GHSA-h4hr-7fg3-h35w
Weakness: CWE-400
Updated: 2026-11-02

OSVROOT-APP-NPM-CVE-2021-23341 No score

CVE-2021-23341 in prismjs - Patched by Root

Root has patched CVE-2021-23341 in the prismjs package for Root:npm. Multiple fixed versions available.

Record: ROOT-APP-NPM-CVE-2021-23341
Updated: 2026-11-02

Affected products

prismjs prism

Affected packages

Affected packages
Package	Affected	Fixed
`prismjs` npm	before 1.23.0	1.23.0
`prismjs` TuxCare:npm From an advisory covering 6 CVEs	1.17.1-tuxcare.0 up to 1.17.1-tuxcare.1, plus listed versions 1.17.1	1.17.1-tuxcare.1
`node-prismjs` Debian:12	before 1.23.0+dfsg-1	1.23.0+dfsg-1
`node-prismjs` Debian:13	before 1.23.0+dfsg-1	1.23.0+dfsg-1
`node-prismjs` Debian:14	before 1.23.0+dfsg-1	1.23.0+dfsg-1
`prismjs` Root:npm	before 1.17.1-aikido.1	1.17.1-aikido.1
`@rootio/prismjs` Root:npm	before 1.17.1-root.io.1	1.17.1-root.io.1
`node-prismjs` Ubuntu:20.04:LTS	All versions, plus listed versions 1.11.0+dfsg-21.11.0+dfsg-3	None known
`node-prismjs` Ubuntu:22.04:LTS	All versions, plus listed versions 1.23.0+dfsg-11.25.0+dfsg-11.27.0+dfsg+~1.26.0-1	None known
`node-prismjs` Ubuntu:24.04:LTS	All versions, plus listed versions 1.29.0+dfsg+~1.26.0-1	None known
`node-prismjs` Ubuntu:25.10	All versions, plus listed versions 1.29.0+dfsg+~1.26.0-11.30.0+dfsg+~1.26.5-1	None known
`node-prismjs` Ubuntu:26.10	All versions, plus listed versions 1.30.0+dfsg+~1.26.6-1	None known
`node-prismjs` Ubuntu:26.04:LTS	All versions, plus listed versions 1.30.0+dfsg+~1.26.5-11.30.0+dfsg+~1.26.5-21.30.0+dfsg+~1.26.6-1	None known

History

History
Recorded	Changed	Sources
Nov 6, 2026	affected, facts
Nov 3, 2026	aliases, published	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-23341 is a high vulnerability (CVSS 7.5) in Prismjs Prism, published February 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.17%, the 88th percentile. Fixed in prismjs 1.23.0.

References

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