CVE-2026-16377
published 2026-07-21CVE-2026-16377: Mitigation bypass in the PDF Viewer component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
PriorityP354critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.39%
31.3th percentile
Mitigation bypass in the PDF Viewer component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 153 | Firefox 153 |
| mozilla | firefox | < 140.13.0 | 140.13.0 |
| mozilla | firefox | < 153.0.0 | 153.0.0 |
| mozilla | firefox | — | — |
| mozilla | firefox_esr | < Firefox ESR 140.13 | Firefox ESR 140.13 |
| mozilla | thunderbird | < Thunderbird 153 | Thunderbird 153 |
| mozilla | thunderbird | < Thunderbird 140.13 | Thunderbird 140.13 |
| mozilla | thunderbird | < 140.13.0 | 140.13.0 |
| mozilla | thunderbird | — | — |
| mozilla | thunderbird | >= 141.0 < 153.0 | 153.0 |
| rhel10 | firefox-flatpak | — | — |
| rhel10 | thunderbird-flatpak | — | — |
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: Mitigation bypass in the PDF Viewer component
vendor_redhat·2026-07-21·CVSS 9.8
CVE-2026-16377 [CRITICAL] firefox: thunderbird: Mitigation bypass in the PDF Viewer component
firefox: thunderbird: Mitigation bypass in the PDF Viewer component
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Mitigation bypass in the PDF Viewer 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 Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of support scope
Package: thunderbird (Red Hat Enterprise Linux 6) - Out of support scope
Package: firefox (R
Mozilla
Mozilla Foundation Security Advisory 2026-71: CVE-2026-16377
vendor_mozilla
CVE-2026-16377 Mozilla Foundation Security Advisory 2026-71: CVE-2026-16377
Mozilla Foundation Security Advisory 2026-71
CVE: CVE-2026-16377
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153
Mozilla
Mozilla Foundation Security Advisory 2026-72: CVE-2026-16377
vendor_mozilla
CVE-2026-16377 Mozilla Foundation Security Advisory 2026-72: CVE-2026-16377
Mozilla Foundation Security Advisory 2026-72
CVE: CVE-2026-16377
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.13
Mozilla
Mozilla Foundation Security Advisory 2026-68: CVE-2026-16377
vendor_mozilla
CVE-2026-16377 Mozilla Foundation Security Advisory 2026-68: CVE-2026-16377
Mozilla Foundation Security Advisory 2026-68
CVE: CVE-2026-16377
Product: Firefox
Impact: high
Fixed in: Firefox 153
Mozilla
Mozilla Foundation Security Advisory 2026-70: CVE-2026-16377
vendor_mozilla
CVE-2026-16377 Mozilla Foundation Security Advisory 2026-70: CVE-2026-16377
Mozilla Foundation Security Advisory 2026-70
CVE: CVE-2026-16377
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.13
GHSA
Mitigation bypass in the PDF Viewer component.
ghsa_unreviewed·2026-07-21
CVE-2026-16377 [CRITICAL] CWE-693 Mitigation bypass in the PDF Viewer component.
Mitigation bypass in the PDF Viewer component. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-16377 firefox: thunderbird: Mitigation bypass in the PDF Viewer component
bugzilla·2026-07-21·CVSS 9.8
CVE-2026-16377 [CRITICAL] CVE-2026-16377 firefox: thunderbird: Mitigation bypass in the PDF Viewer component
CVE-2026-16377 firefox: thunderbird: Mitigation bypass in the PDF Viewer component
Mitigation bypass in the PDF Viewer component. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.
Bugzilla
CVE-2026-53196 kernel: USB: serial: io_ti: fix heap overflow in get_manuf_info()
bugzilla·2026-06-25
CVE-2026-53196 [HIGH] CVE-2026-53196 kernel: USB: serial: io_ti: fix heap overflow in get_manuf_info()
CVE-2026-53196 kernel: USB: serial: io_ti: fix heap overflow in get_manuf_info()
In the Linux kernel, the following vulnerability has been resolved:
USB: serial: io_ti: fix heap overflow in get_manuf_info()
get_manuf_info() reads le16_to_cpu(rom_desc->Size) bytes from the
device I2C EEPROM into a buffer allocated with kmalloc_obj(), which
is sizeof(struct edge_ti_manuf_descriptor) = 10 bytes.
The Size field comes from the device and is only validated (in
check_i2c_image()) to make sure the descriptor fits within
TI_MAX_I2C_SIZE (16384 bytes), not against the destination buffer size.
A malicious USB device can therefore set Size to any value up to 16377,
causing a heap overflow of up to 16367 bytes when plugged into a host
running this driver.
valid_csum() is called after read_rom() an
2026-07-21
Published