How severe is CVE-2021-43308?

CVE-2021-43308 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-43308 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43308?

CVE-2021-43308 primarily affects Markdown-link-extractor Project Markdown-link-extractor. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-43308?

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

When was CVE-2021-43308 published?

CVE-2021-43308 was published on 2022-06-02 and last updated on 2026-06-17.

CVE-2021-43308

CVE-2021-43308 is a medium-severity vulnerability in Markdown-link-extractor Project Markdown-link-extractor with a CVSS 3.x base score of 5.9. 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 5.9)
CVSS v2: 5.0
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Markdown-link-extractor Project Markdown-link-extractor
Published: 2022-06-02
Last modified: 2026-06-17

Description

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the markdown-link-extractor npm package, when an attacker is able to supply arbitrary input to the module's exported function

Frequently asked questions

What is CVE-2021-43308?: An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the markdown-link-extractor npm package, when an attacker is able to supply arbitrary input to the module's exported function
How severe is CVE-2021-43308?: CVE-2021-43308 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-43308 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43308?: CVE-2021-43308 primarily affects Markdown-link-extractor Project Markdown-link-extractor. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-43308?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-43308 published?: CVE-2021-43308 was published on 2022-06-02 and last updated on 2026-06-17.

References

https://research.jfrog.com/vulnerabilities/markdown-link-extractor-redos-xray-211350/

Affected products (2)

cpe:2.3:a:markdown-link-extractor_project:markdown-link-extractor:*:*:*:*:*:node.js:*:*
cpe:2.3:a:markdown-link-extractor_project:markdown-link-extractor:4.0.0:*:*:*:*:node.js:*:*

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