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Fencer Vulns
critical 9.8

CVE-2021-23639 json

Remote Code Execution (RCE)

published 2021-12-10 4 y ago modified 2026-07-08 4 mo ago also GHSA-x949-7cm6-fm6p , EUVD-2021-2610

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
5.4%
EPSS 5.4% chance of exploitation in 30 days, percentile 92%
public exploits
0
none known

Summary

The package md-to-pdf before 5.0.0 are vulnerable to Remote Code Execution (RCE) due to utilizing the library gray-matter to parse front matter content, without disabling the JS engine.

Patch / fix

  • npm md-to-pdf 5.0.0
  • n/a md-to-pdf 5.0.0

Exploit prediction

5.41% chance of exploitation in the next 30 days, higher than 92% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • snyk.io https://snyk.io/vuln/SNYK-JS-MDTOPDF-1657880 referenced PoC, tagged "exploit" by a source, unverified
  • github.com https://github.com/simonhaenisch/md-to-pdf/issues/99 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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
GitHub 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem package affected fixed in
npm md-to-pdf
<5.0.0
5.0.0

Affected products

  • n/a md-to-pdf

Classification

Weakness
  • CWE-94 Improper Control of Generation of Code

References

Sources

Fencer Vulns 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.