How severe is CVE-2022-34749?

CVE-2022-34749 has a CVSS 3.x base score of 7.5, rated high 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 high.

Is CVE-2022-34749 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-34749?

CVE-2022-34749 primarily affects Mistune Project Mistune. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-34749?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2022-34749 published?

CVE-2022-34749 was published on 2022-07-25 and last updated on 2026-06-17.

CVE-2022-34749

CVE-2022-34749 is a high-severity vulnerability in Mistune Project Mistune with a CVSS 3.x base score of 7.5. 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: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Mistune Project Mistune
Published: 2022-07-25
Last modified: 2026-06-17

Description

In mistune through 2.0.2, support of inline markup is implemented by using regular expressions that can involve a high amount of backtracking on certain edge cases. This behavior is commonly named catastrophic backtracking.

Frequently asked questions

What is CVE-2022-34749?: In mistune through 2.0.2, support of inline markup is implemented by using regular expressions that can involve a high amount of backtracking on certain edge cases. This behavior is commonly named catastrophic backtracking.
How severe is CVE-2022-34749?: CVE-2022-34749 has a CVSS 3.x base score of 7.5, rated high 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 high.
Is CVE-2022-34749 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-34749?: CVE-2022-34749 primarily affects Mistune Project Mistune. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-34749?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2022-34749 published?: CVE-2022-34749 was published on 2022-07-25 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:mistune_project:mistune:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*

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