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Fencer Intel
critical 9.8

CVE-2021-40531 in the critical feed json

Sketch before 75 allows library feeds to be used to bypass file quarantine.

published 5y ago modified 4mo ago also EUVD-2021-27706

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
33.0%
EPSS 33.0% chance of exploitation in 30 days, percentile 98%
public exploits
0
none known

Summary

Sketch before 75 allows library feeds to be used to bypass file quarantine. Files are automatically downloaded and opened, without the com.apple.quarantine extended attribute. This results in remote code execution, as demonstrated by CommandString in a terminal profile to Terminal.app.

Patch / fix

  • sketch sketch 75

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Exploit prediction

33.00% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • jonpalmisc.com https://jonpalmisc.com/2021/11/22/cve-2021-40531 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-434 Unrestricted Upload of File with Dangerous Type

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.