SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-24045

A type confusion vulnerability could be triggered when resolving the "typeof" unary operator in Facebook Hermes prior to v0.10.0.

CRITICAL 9.8EPSS 1.21%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.21%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A type confusion vulnerability could be triggered when resolving the "typeof" unary operator in Facebook Hermes prior to v0.10.0. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.21% probability · 67th percentile
CISA KEV
Not listed
Weakness
CWE-843
Affected
facebook/hermes
Source
cve-assign@fb.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.