CVE-2026-50873

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-15 · updated 2026-06-17
Weakness: CWE-434

Description

An arbitrary file upload vulnerability in the attachment handling component of flatnotes v5.5.4 allows attackers to execute arbitrary code via uploading a crafted HTML or SVG file.

References

https://gist.github.com/pyuysig/ab0af5b10877fb906941e05a69b202a7
https://gist.github.com/pyuysig/ab0af5b10877fb906941e05a69b202a7

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