Vulnerability · Published Sep 9, 2020 · Assigned by facebook

CVE-2020-1912

High 8.1

In plain English

A high-severity out-of-bounds write in Hermes from Facebook. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.8% (higher than 79% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)8.1High

Exploit odds (30 days)1.8%top 21.2% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

An out-of-bounds read/write vulnerability when executing lazily compiled inner generator functions in Facebook Hermes prior to commit 091835377369c8fd5917d9b87acffa721ad2a168 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	hermes-engine	0.5.2	GHSA-pf27-929j-9pmm

Affected products (as reported)

Vendor	Product	Versions
Facebook	Hermes	commit prior to 091835377369c8fd5917d9b87acffa721ad2a168

Weakness: CWE-787

References

https://www.facebook.com/security/advisories/cve-2020-1912 x_refsource_CONFIRM
https://github.com/facebook/hermes/commit/091835377369c8fd5917d9b87acffa721ad2a168 x_refsource_CONFIRM