Medium 5.9Published Aug 1, 2023

CVE-2023-4049Race conditions in reference counting code were found through code inspection.

Updated under an hour ago (Oct 26, 2026, 1:20 PM ET)

Does this affect you?

It affects mozilla firefox and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for mozilla firefox

Exploited in the last 30 days

Race conditions in reference counting code were found through code inspection. These could have resulted in potentially exploitable use-after-free vulnerabilities. This vulnerability affects Firefox < 116, Firefox ESR < 102.14, and Firefox ESR < 115.1.

CVSS: 5.9 MEDIUM (v3.1, NVD)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-362
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Modified
Record last updated: Oct 23, 2026
First seen by InfoSec Signals: Oct 23, 2026

Affected products

Affected products

mozilla firefox mozilla:firefox	before 116.0; from 102.0 before 102.14; from 115.0 before 115.1	NVD
debian debian_linux debian:debian_linux	11.0; 12.0	NVD

References

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1842658	issue-tracking, permissions-required
https://lists.debian.org/debian-lts-announce/2023/08/msg00008.html
https://lists.debian.org/debian-lts-announce/2023/08/msg00010.html
https://www.debian.org/security/2023/dsa-5464	third-party-advisory
https://www.debian.org/security/2023/dsa-5469	third-party-advisory
https://www.mozilla.org/security/advisories/mfsa2023-29/	vendor-advisory
https://www.mozilla.org/security/advisories/mfsa2023-30/	vendor-advisory
https://www.mozilla.org/security/advisories/mfsa2023-31/	vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.