CVE-2020-1911
A type confusion vulnerability when resolving properties of JavaScript objects with specially-crafted prototype chains in Facebook Hermes prior to commit fe52854cdf6725c2eaa9e125995da76e6ceb27da allows attackers to potentially execute arbitrary code via…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.00%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A type confusion vulnerability when resolving properties of JavaScript objects with specially-crafted prototype chains in Facebook Hermes prior to commit fe52854cdf6725c2eaa9e125995da76e6ceb27da 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.
- 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
- 2.00% probability · 81th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-843
- Affected
- facebook/hermes
- Source
- cve-assign@fb.com
EPSS 2.0% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://github.com/facebook/hermes/commit/fe52854cdf6725c2eaa9e125995da76e6ceb27daPatch, Third Party Advisory
- https://www.facebook.com/security/advisories/cve-2020-1911Third Party Advisory
- https://github.com/facebook/hermes/commit/fe52854cdf6725c2eaa9e125995da76e6ceb27daPatch, Third Party Advisory
- https://www.facebook.com/security/advisories/cve-2020-1911Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.