CVE-2021-47837

CVE-2021-47837 is a high-severity vulnerability with a CVSS 3.x base score of 7.2. 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-79.

Key facts

Description

Markdownify 1.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload crafted markdown files with embedded scripts that execute when the file is opened, potentially enabling remote code execution.

Frequently asked questions

What is CVE-2021-47837?
Markdownify 1.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload crafted markdown files with embedded scripts that execute when the file is opened, potentially enabling remote code execution.
How severe is CVE-2021-47837?
CVE-2021-47837 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-47837 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-47837?
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.
Does CVE-2021-47837 have an EU (EUVD) identifier?
Yes. CVE-2021-47837 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2886.
When was CVE-2021-47837 published?
CVE-2021-47837 was published on 2026-01-16 and last updated on 2026-06-17.

References

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

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