How severe is CVE-2021-32821?

CVE-2021-32821 has a CVSS 3.x base score of 6.2, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-32821 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32821?

CVE-2021-32821 affects Mootools. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32821?

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

When was CVE-2021-32821 published?

CVE-2021-32821 was published on 2023-01-03 and last updated on 2026-06-17.

CVE-2021-32821

CVE-2021-32821 is a medium-severity vulnerability in Mootools with a CVSS 3.x base score of 6.2. 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-1333.

Key facts

Severity: Medium (CVSS 3.x base score 6.2)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Mootools
Published: 2023-01-03
Last modified: 2026-06-17

Description

MooTools is a collection of JavaScript utilities for JavaScript developers. All known versions include a CSS selector parser that is vulnerable to Regular Expression Denial of Service (ReDoS). An attack requires that an attacker can inject a string into a CSS selector at runtime, which is quite common with e.g. jQuery CSS selectors. No patches are available for this issue.

Frequently asked questions

What is CVE-2021-32821?: MooTools is a collection of JavaScript utilities for JavaScript developers. All known versions include a CSS selector parser that is vulnerable to Regular Expression Denial of Service (ReDoS). An attack requires that an attacker can inject a string into a CSS selector at runtime, which is quite common with e.g. jQuery CSS selectors. No patches are available for this issue.
How severe is CVE-2021-32821?: CVE-2021-32821 has a CVSS 3.x base score of 6.2, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-32821 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32821?: CVE-2021-32821 affects Mootools. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32821?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-32821 published?: CVE-2021-32821 was published on 2023-01-03 and last updated on 2026-06-17.

References

https://securitylab.github.com/advisories/GHSL-2020-345-redos-mootools/

Affected products (1)

cpe:2.3:a:mootools:mootools:*:*:*:*:*:*:*:*

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