CVE-2026-16389
published 2026-07-21CVE-2026-16389: Incorrect boundary conditions, integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
PriorityP350critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.42%
34.6th percentile
Incorrect boundary conditions, integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 153 | Firefox 153 |
| mozilla | firefox | < 153.0.0 | 153.0.0 |
| mozilla | thunderbird | < Thunderbird 153 | Thunderbird 153 |
| mozilla | thunderbird | < 153.0 | 153.0 |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat9.8CRITICAL
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Red Hat
firefox: thunderbird: Incorrect boundary conditions, integer overflow in the Libraries component in NSS
vendor_redhat·2026-07-21·CVSS 9.8
CVE-2026-16389 [CRITICAL] CWE-787 firefox: thunderbird: Incorrect boundary conditions, integer overflow in the Libraries component in NSS
firefox: thunderbird: Incorrect boundary conditions, integer overflow in the Libraries component in NSS
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Incorrect boundary conditions, integer overflow in the Libraries component in NSS
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Not affected
Package: firefox (Red Hat Enterprise Linux 6) - Not affected
Package: thun
Mozilla
Mozilla Foundation Security Advisory 2026-71: CVE-2026-16389
vendor_mozilla
CVE-2026-16389 Mozilla Foundation Security Advisory 2026-71: CVE-2026-16389
Mozilla Foundation Security Advisory 2026-71
CVE: CVE-2026-16389
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153
Mozilla
Mozilla Foundation Security Advisory 2026-68: CVE-2026-16389
vendor_mozilla
CVE-2026-16389 Mozilla Foundation Security Advisory 2026-68: CVE-2026-16389
Mozilla Foundation Security Advisory 2026-68
CVE: CVE-2026-16389
Product: Firefox
Impact: high
Fixed in: Firefox 153
GHSA
Incorrect boundary conditions, integer overflow in the Libraries component in NSS.
ghsa_unreviewed·2026-07-21
CVE-2026-16389 [CRITICAL] CWE-190 Incorrect boundary conditions, integer overflow in the Libraries component in NSS.
Incorrect boundary conditions, integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 153.
No detection rules found.
No public exploits indexed.
2026-07-21
Published