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Fencer Intel
critical 9.6

CVE-2021-29996 json

Mark Text through 0.16.3 allows attackers arbitrary command execution.

published 5y ago modified 4mo ago also EUVD-2021-16455

cvss
9.6
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.8%
EPSS 2.8% chance of exploitation in 30 days, percentile 86%
public exploits
0
none known

Summary

Mark Text through 0.16.3 allows attackers arbitrary command execution. This could lead to Remote Code Execution (RCE) by opening .md files containing a mutation Cross Site Scripting (XSS) payload.

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Exploit prediction

2.75% chance of exploitation in the next 30 days, higher than 86% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/marktext/marktext/issues/2548 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 9.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
NVD 2.0 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

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.