CVE-2026-12291
published 2026-06-16CVE-2026-12291: Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and…
PriorityP346high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.38%
30.4th percentile
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 152 | Firefox 152 |
| mozilla | firefox | < 115.37.0 | 115.37.0 |
| mozilla | firefox | < 152.0.0 | 152.0.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 128.0 < 140.12.0 | 140.12.0 |
| mozilla | firefox_esr | < Firefox ESR 140.12 | Firefox ESR 140.12 |
| mozilla | firefox_esr | < Firefox ESR 115.37 | Firefox ESR 115.37 |
| mozilla | thunderbird | < Thunderbird 140.12 | Thunderbird 140.12 |
| mozilla | thunderbird | < Thunderbird 152 | Thunderbird 152 |
| mozilla | thunderbird | < 140.12.0 | 140.12.0 |
| mozilla | thunderbird | < 152.0.0 | 152.0.0 |
| mozilla | thunderbird | — | — |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat7.5HIGH
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Red Hat
firefox: thunderbird: Use-after-free in the Networking: HTTP component
vendor_redhat·2026-06-16·CVSS 7.5
CVE-2026-12291 [HIGH] CWE-825 firefox: thunderbird: Use-after-free in the Networking: HTTP component
firefox: thunderbird: Use-after-free in the Networking: HTTP component
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Use-after-free in the Networking: HTTP component
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) - Affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: thunderbird (Red Hat Enterprise Li
Mozilla
Mozilla Foundation Security Advisory 2026-58: CVE-2026-12291
vendor_mozilla
CVE-2026-12291 Mozilla Foundation Security Advisory 2026-58: CVE-2026-12291
Mozilla Foundation Security Advisory 2026-58
CVE: CVE-2026-12291
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-57: CVE-2026-12291
vendor_mozilla
CVE-2026-12291 Mozilla Foundation Security Advisory 2026-57: CVE-2026-12291
Mozilla Foundation Security Advisory 2026-57
CVE: CVE-2026-12291
Product: Firefox
Impact: high
Fixed in: Firefox 152
Mozilla
Mozilla Foundation Security Advisory 2026-61: CVE-2026-12291
vendor_mozilla
CVE-2026-12291 Mozilla Foundation Security Advisory 2026-61: CVE-2026-12291
Mozilla Foundation Security Advisory 2026-61
CVE: CVE-2026-12291
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.12
Mozilla
Mozilla Foundation Security Advisory 2026-59: CVE-2026-12291
vendor_mozilla
CVE-2026-12291 Mozilla Foundation Security Advisory 2026-59: CVE-2026-12291
Mozilla Foundation Security Advisory 2026-59
CVE: CVE-2026-12291
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 115.37
Mozilla
Mozilla Foundation Security Advisory 2026-60: CVE-2026-12291
vendor_mozilla
CVE-2026-12291 Mozilla Foundation Security Advisory 2026-60: CVE-2026-12291
Mozilla Foundation Security Advisory 2026-60
CVE: CVE-2026-12291
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 152
VulDB
Mozilla Firefox up to 151 HTTP use after free (Nessus ID 321204)
vuldb·2026-06-17
CVE-2026-12291 [CRITICAL] Mozilla Firefox up to 151 HTTP use after free (Nessus ID 321204)
A vulnerability classified as critical was found in Mozilla Firefox up to 151. Affected by this vulnerability is an unknown functionality of the component HTTP. Such manipulation leads to use after free.
This vulnerability is traded as CVE-2026-12291. The attack may be launched remotely. There is no exploit available.
Upgrading the affected component is advised.
GHSA
Use-after-free in the Networking: HTTP component.
ghsa_unreviewed·2026-06-16
CVE-2026-12291 Use-after-free in the Networking: HTTP component.
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2036929https://www.mozilla.org/security/advisories/mfsa2026-57/https://www.mozilla.org/security/advisories/mfsa2026-58/https://www.mozilla.org/security/advisories/mfsa2026-59/https://www.mozilla.org/security/advisories/mfsa2026-60/https://www.mozilla.org/security/advisories/mfsa2026-61/https://access.redhat.com/errata/RHSA-2026:27717https://access.redhat.com/errata/RHSA-2026:27733https://access.redhat.com/errata/RHSA-2026:27734https://access.redhat.com/errata/RHSA-2026:29940https://access.redhat.com/errata/RHSA-2026:30846https://access.redhat.com/errata/RHSA-2026:33445https://access.redhat.com/errata/RHSA-2026:36100https://access.redhat.com/errata/RHSA-2026:36101https://access.redhat.com/errata/RHSA-2026:36102https://access.redhat.com/errata/RHSA-2026:36103https://access.redhat.com/errata/RHSA-2026:37210https://access.redhat.com/errata/RHSA-2026:37391https://access.redhat.com/errata/RHSA-2026:38506https://access.redhat.com/errata/RHSA-2026:38750https://access.redhat.com/errata/RHSA-2026:38751https://access.redhat.com/errata/RHSA-2026:38753https://access.redhat.com/errata/RHSA-2026:39011https://access.redhat.com/errata/RHSA-2026:39141https://access.redhat.com/errata/RHSA-2026:39142https://access.redhat.com/errata/RHSA-2026:39428https://access.redhat.com/errata/RHSA-2026:39706https://access.redhat.com/security/cve/CVE-2026-12291https://bugzilla.redhat.com/show_bug.cgi?id=2489244https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12291.json
2026-06-16
Published