What is CVE-2023-37456?

CVE-2023-37456 is a medium-severity vulnerability in Mozilla Firefox, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2023-07-12.

How severe is CVE-2023-37456?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Is CVE-2023-37456 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

NULL pointer dereference in Mozilla Firefox

CVE-2023-37456

The session restore helper crashed whenever there was no parameter sent to the message handler. This vulnerability affects Firefox for iOS < 115.

Published 2023-07-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.005 (40.6th percentile), scored 2026-10-20.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 40.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Mozilla Firefox
Mozilla Firefox For iOS — versions unspecified

Weakness classification (CWE)

CWE-476 — NULL Pointer Dereference

Public proof-of-concept exploits

References

bugzilla.mozilla.org/show_bug.cgi (Issue Tracking, Vendor Advisory)
www.mozilla.org/security/advisories/mfsa2023-25/ (Vendor Advisory)

Frequently asked questions

What is CVE-2023-37456?: CVE-2023-37456 is a medium-severity vulnerability in Mozilla Firefox, classified under NULL Pointer Dereference. CVSS score: 6.5/10. Published 2023-07-12.
How severe is CVE-2023-37456?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2023-37456 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.