Skip to content
Fencer Vulns
critical 9.8

CVE-2020-1896 json

A stack overflow vulnerability in Facebook Hermes 'builtin apply' prior to commit 86543ac47e59c522976b5632b8bf9a2a4583c7d2 (https://github.…

published 2021-02-02 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-12722

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.5%
EPSS 2.5% chance of exploitation in 30 days, percentile 84%
public exploits
0
none known

Summary

A stack overflow vulnerability in Facebook Hermes 'builtin apply' prior to commit 86543ac47e59c522976b5632b8bf9a2a4583c7d2 (https://github.com/facebook/hermes/commit/86543ac47e59c522976b5632b8bf9a2a4583c7d2) allows attackers to potentially execute arbitrary code via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.

Patch / fix

  • facebook hermes 0.5.0

Exploit prediction

2.52% chance of exploitation in the next 30 days, higher than 84% of all scored CVEs (FIRST EPSS, 2026-11-08).

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 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

  • Facebook Hermes

Classification

Weakness

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.