CVE-2020-1914
A logic vulnerability when handling the SaveGeneratorLong instruction in Facebook Hermes prior to commit b2021df620824627f5a8c96615edbd1eb7fdddfc allows attackers to potentially read out of bounds or theoretically execute arbitrary code via crafted…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.51%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A logic vulnerability when handling the SaveGeneratorLong instruction in Facebook Hermes prior to commit b2021df620824627f5a8c96615edbd1eb7fdddfc allows attackers to potentially read out of bounds or theoretically 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
- 2.51% probability · 85th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-670
- Affected
- facebook/hermes
- Source
- cve-assign@fb.com
EPSS 2.5% 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/b2021df620824627f5a8c96615edbd1eb7fdddfcPatch, Third Party Advisory
- https://www.facebook.com/security/advisories/cve-2020-1914Vendor Advisory
- https://github.com/facebook/hermes/commit/b2021df620824627f5a8c96615edbd1eb7fdddfcPatch, Third Party Advisory
- https://www.facebook.com/security/advisories/cve-2020-1914Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.