How severe is CVE-2022-21670?

CVE-2022-21670 has a CVSS 3.x base score of 5.3, rated medium 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 low.

Is CVE-2022-21670 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-21670?

CVE-2022-21670 affects Markdown-it Project Markdown-it. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-21670?

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

When was CVE-2022-21670 published?

CVE-2022-21670 was published on 2022-01-10 and last updated on 2026-06-17.

CVE-2022-21670

CVE-2022-21670 is a medium-severity vulnerability in Markdown-it Project Markdown-it with a CVSS 3.x base score of 5.3. 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 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Markdown-it Project Markdown-it
Published: 2022-01-10
Last modified: 2026-06-17

Description

markdown-it is a Markdown parser. Prior to version 1.3.2, special patterns with length greater than 50 thousand characterss could slow down the parser significantly. Users should upgrade to version 12.3.2 to receive a patch. There are no known workarounds aside from upgrading.

Frequently asked questions

What is CVE-2022-21670?: markdown-it is a Markdown parser. Prior to version 1.3.2, special patterns with length greater than 50 thousand characterss could slow down the parser significantly. Users should upgrade to version 12.3.2 to receive a patch. There are no known workarounds aside from upgrading.
How severe is CVE-2022-21670?: CVE-2022-21670 has a CVSS 3.x base score of 5.3, rated medium 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 low.
Is CVE-2022-21670 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-21670?: CVE-2022-21670 affects Markdown-it Project Markdown-it. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-21670?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-21670 published?: CVE-2022-21670 was published on 2022-01-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:markdown-it_project:markdown-it:*:*:*:*:*:*:*:*

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