TI-2021-06353 Aliases CVE-2021-24037 GHSA-mph8-6787-r8hw

Use after free in Meta Hermes

MEDIUM 46CWE-416Published 2021-06-15 · Updated 2024-08-03

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-416 and the CVSS impact.

Summary

A use after free in hermes, while emitting certain error messages, prior to commit d86e185e485b6330216dee8e854455c694e3a36e 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.

Why it matters now

EPSS 0.01795 78th percentileScored 2026-11-07

Fix Fixed hermes-engine (npm): 0.8.0

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Meta	Hermes	commit prior to d86e185e485b6330216dee8e854455c694e3a36e	—	No fix listed	CNA
—	hermes-engine (npm)	before 0.8.0	0.8.0	Patch available	GHSA-mph8-6787-r8hw

Hermes VendorMeta Affected commit prior to d86e185e485b6330216dee8e854455c694e3a36e Fixed in — No fix listed CNA
hermes-engine (npm) Vendor— Affected before 0.8.0 Fixed in 0.8.0 Patch available GHSA-mph8-6787-r8hw

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:facebook:hermes::::::::	before 0.8.0	Vulnerable	Meta

cpe:2.3:a:facebook:hermes:*:*:*:*:*:*:*:* Versions before 0.8.0 Vulnerable ·Meta

Remediation

Fix · GHSA-mph8-6787-r8hw hermes-engine (npm) Fixed in 0.8.0 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2021-24037
2026-10-03 Alias added: GHSA-mph8-6787-r8hw

References

Patch 1

https://github.com/facebook/hermes/commit/d86e185e485b6330216dee8e854455c694e3a36e

Advisory 2

Other 1

https://github.com/facebook/hermes

TI-2023-14306 Use after free in Meta Hermes CVSS 3.1CRITICAL 9.8
TI-2023-12661 Use after free in Meta Hermes CVSS 3.1CRITICAL 9.8
TI-2023-11181 Type confusion in Meta Hermes CVSS 3.1CRITICAL 9.8
TI-2023-09388 Type confusion in Meta Hermes CVSS 3.1CRITICAL 9.8
TI-2023-09387 Out-of-bounds write in Meta Hermes CVSS 3.1CRITICAL 9.8
TI-2020-01841 A logic vulnerability when handling the SaveGeneratorLong instruction in Facebook Hermes… CVSS 3.1CRITICAL 9.8

See all 19 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences