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.

CVSS v4.0

5.1 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v3.1

7.2 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

EPSS

0.42% chance of exploitation in the next 30 days, 35th percentile

Published

2026-01-16

Updated

2026-03-05

Proof-of-concept exploits (2)

• https://www.exploit-db.com/exploits/49835
• https://imgur.com/a/T4jBoiS

References

• CVE Record
• NVD entry

Related

• CVE-2021-47836
• CVE-2021-47838
• CVE-2021-47835
• CVE-2021-47839
• CVE-2021-47834
• CVE-2021-47840