How severe is CVE-2023-30470?

CVE-2023-30470 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-30470 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-30470?

CVE-2023-30470 affects Facebook Hermes. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-30470?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2023-30470 published?

CVE-2023-30470 was published on 2023-05-18 and last updated on 2026-06-17.

CVE-2023-30470

CVE-2023-30470 is a critical-severity vulnerability in Facebook Hermes with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Facebook Hermes
Published: 2023-05-18
Last modified: 2026-06-17

Description

A use-after-free related to unsound inference in the bytecode generation when optimizations are enabled for Hermes prior to commit da8990f737ebb9d9810633502f65ed462b819c09 could have been used by an attacker to achieve remote code execution. Note that this is only exploitable in cases where Hermes is used to execute untrusted JavaScript. Hence, most React Native applications are not affected.

Frequently asked questions

What is CVE-2023-30470?: A use-after-free related to unsound inference in the bytecode generation when optimizations are enabled for Hermes prior to commit da8990f737ebb9d9810633502f65ed462b819c09 could have been used by an attacker to achieve remote code execution. Note that this is only exploitable in cases where Hermes is used to execute untrusted JavaScript. Hence, most React Native applications are not affected.
How severe is CVE-2023-30470?: CVE-2023-30470 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-30470 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-30470?: CVE-2023-30470 affects Facebook Hermes. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-30470?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-30470 published?: CVE-2023-30470 was published on 2023-05-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:facebook:hermes:-:*:*:*:*:*:*:*

More vulnerabilities in Facebook Hermes

CVE-2023-28081 — Critical (CVSS 9.8): A bytecode optimization bug in Hermes prior to commit e6ed9c1a4b02dc219de1648f44cd808a56171b81 could be used to cause…
CVE-2023-25933 — Critical (CVSS 9.8): A type confusion bug in TypedArray prior to commit e6ed9c1a4b02dc219de1648f44cd808a56171b81 could have been used by a…
CVE-2023-23557 — Critical (CVSS 9.8): An error in Hermes' algorithm for copying objects properties prior to commit a00d237346894c6067a594983be6634f4168c9ad…
CVE-2023-23556 — Critical (CVSS 9.8): An error in BigInt conversion to Number in Hermes prior to commit a6dcafe6ded8e61658b40f5699878cd19a481f80 could have…
CVE-2022-40138 — Critical (CVSS 9.8): An integer conversion error in Hermes bytecode generation, prior to commit 6aa825e480d48127b480b08d13adf70033237097,…
CVE-2022-35289 — Critical (CVSS 9.8): A write-what-where condition in hermes caused by an integer overflow, prior to commit…

All CVEs affecting Facebook Hermes →

Other CWE-416 (Use After Free) vulnerabilities

CVE-2026-13782 — Critical (CVSS 10.0): Use after free in Browser in Google Chrome prior to 150.0.7871.47 allowed a remote attacker who had compromised the…
CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

Browse all CWE-416 (Use After Free) vulnerabilities →