CVE-2021-23424
Regular Expression Denial of Service (ReDoS)
This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
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
What each source reports
CVE List Score used
Regular Expression Denial of Service (ReDoS)
This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
- Record
CVE-2021-23424- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P - Updated
- 2026-11-02
EUVDEUVD-2021-2126
This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
- Record
EUVD-2021-2126- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-whgm-jr23-g3j9
Uncontrolled Resource Consumption in ansi-html
This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
- Record
GHSA-whgm-jr23-g3j9- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
NVD
This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
- Record
CVE-2021-23424- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Updated
- 2026-11-02
OSVGHSA-whgm-jr23-g3j9
Uncontrolled Resource Consumption in ansi-html
This affects all versions of package ansi-html. If an attacker provides a malicious string, it will get stuck processing the input for an extremely long time.
- Record
GHSA-whgm-jr23-g3j9- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVROOT-APP-NPM-CVE-2021-23424 No score
CVE-2021-23424 in ansi-html - Patched by Root
Root has patched CVE-2021-23424 in the ansi-html package for Root:npm. Multiple fixed versions available.
- Record
ROOT-APP-NPM-CVE-2021-23424- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
ansi-htmlnpm |
before 0.0.8 | 0.0.8 |
ansi-htmlRoot:npm |
before 0.0.7-aikido.1 | 0.0.7-aikido.1 |
@rootio/ansi-htmlRoot:npm |
before 0.0.7-root.io.1 | 0.0.7-root.io.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-23424 is a high vulnerability (CVSS 7.5) in Ansi-html Project Ansi-html, published August 18, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.77%, the 78th percentile. Fixed in ansi-html 0.0.8.
References
github.com/Tjatse/ansi-html/issues/19
snyk.io/vuln/SNYK-JS-ANSIHTML-1296849
nvd.nist.gov/vuln/detail/CVE-2021-23424