What is CVE-2025-46656?

python-markdownify (aka markdownify) before 0.14.1 allows large headline prefixes such as in addition to through . This causes memory consumption.

How severe is CVE-2025-46656?

CVE-2025-46656 has a CVSS 3.x base score of 2.9, rated low severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2025-46656 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-46656?

CVE-2025-46656 affects Matthewwithanm Markdownify. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-46656?

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

Does CVE-2025-46656 have an EU (EUVD) identifier?

Yes. CVE-2025-46656 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12476.

When was CVE-2025-46656 published?

CVE-2025-46656 was published on 2025-04-26 and last updated on 2026-06-17.

CVE-2025-46656

CVE-2025-46656 is a low-severity vulnerability in Matthewwithanm Markdownify with a CVSS 3.x base score of 2.9. 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-1284.

Key facts

Severity: Low (CVSS 3.x base score 2.9)
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-12476
Weakness: CWE-1284
Affected product: Matthewwithanm Markdownify
Published: 2025-04-26
Last modified: 2026-06-17

Description

python-markdownify (aka markdownify) before 0.14.1 allows large headline prefixes such as <h9999999> in addition to <h1> through <h6>. This causes memory consumption.

Frequently asked questions

What is CVE-2025-46656?: python-markdownify (aka markdownify) before 0.14.1 allows large headline prefixes such as <h9999999> in addition to <h1> through <h6>. This causes memory consumption.
How severe is CVE-2025-46656?: CVE-2025-46656 has a CVSS 3.x base score of 2.9, rated low severity. It is exploitable over local access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2025-46656 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-46656?: CVE-2025-46656 affects Matthewwithanm Markdownify. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-46656?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-46656 have an EU (EUVD) identifier?: Yes. CVE-2025-46656 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12476.
When was CVE-2025-46656 published?: CVE-2025-46656 was published on 2025-04-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:matthewwithanm:markdownify:*:*:*:*:*:python:*:*

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