What is CVE-2023-23557?

CVE-2023-23557 is a critical-severity vulnerability in Facebook Hermes, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 9.8/10. Published 2023-05-18.

How severe is CVE-2023-23557?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Facebook Hermes

CVE-2023-23557

An error in Hermes' algorithm for copying objects properties prior to commit a00d237346894c6067a594983be6634f4168c9ad could be used by a malicious attacker to execute arbitrary code via type confusion. Note that this is only exploitable in cases where Hermes is used to execute untrusted JavaScript. Hence, most React Native applications are not affected.

EPSS: 0.009 (57.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Facebook Hermes — versions 0

Weakness classification (CWE)

CWE-843 — Access of Resource Using Incompatible Type (Type Confusion)

References

cve-assign@fb.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
cve-assign@fb.com (Patch, x_refsource_MISC, Vendor Advisory)

Frequently asked questions

What is CVE-2023-23557?: CVE-2023-23557 is a critical-severity vulnerability in Facebook Hermes, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 9.8/10. Published 2023-05-18.
How severe is CVE-2023-23557?: Critical severity. CVSS v3 base score is 9.8 out of 10.