PatchTheCVECVE-2025-11710: A compromised web process using malicious IPC messages could have caused the privileged browser process to rev
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This month
CRITICAL 9.8REMOTEUPGRADEUPGRADE
CVE-2025-11710 is a critical-severity flaw (CVSS 9.8) affecting firefox, thunderbird. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A compromised web process using malicious IPC messages could have caused the privileged browser process to reveal blocks of its memory to the compromised process. This vulnerability was fixed in Firefox 144, Firefox ESR 115.29, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.
Why this priority
- Critical severity
- CISA SSVC: automatable with total technical impact
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 65%) |
| CISA exploited list | No |
| Weakness | CWE-200 |
| Published | 2025-10-14 |
| Last modified | 2026-10-23 |
Publisher (CNA): Mozilla Corporation · Vendor: mozilla
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
mozilla firefox UPGRADE
Affected: < 115.29.0 · < 144.0 · >= 116.0 and < 140.4.0
Fixed in: 115.29.0, 140.4.0, 144.0
Safe to downgrade to: a release before 116.0
1. Check installed version
apt-cache policy firefox || rpm -q firefox || firefox --version
2. UPGRADE to 115.29.0 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade firefox
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade firefox
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 116.0 (Debian / Ubuntu)
apt-cache madison firefox
sudo apt install firefox=<VERSION_BEFORE_116.0>
sudo apt-mark hold firefox
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list firefox
sudo dnf downgrade firefox-<VERSION_BEFORE_116.0>
sudo dnf versionlock add firefox
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
mozilla thunderbird UPGRADE
Affected: < 140.4.0 · >= 141.0 and < 144.0
Fixed in: 140.4.0, 144.0
Safe to downgrade to: a release before 141.0
1. Check installed version
apt-cache policy thunderbird || rpm -q thunderbird || thunderbird --version
2. UPGRADE to 140.4.0 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade thunderbird
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade thunderbird
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 141.0 (Debian / Ubuntu)
apt-cache madison thunderbird
sudo apt install thunderbird=<VERSION_BEFORE_141.0>
sudo apt-mark hold thunderbird
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list thunderbird
sudo dnf downgrade thunderbird-<VERSION_BEFORE_141.0>
sudo dnf versionlock add thunderbird
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
Exact fixes by distribution
Fedora 46 · python-fontconfig · FIXED · 0.6.3-1.fc46 · FEDORA-2026-f92ca8b01f · source
sudo dnf upgrade --advisory=FEDORA-2026-f92ca8b01f
Fedora ELN · valgrind · FIXED · 3.28.0-1.eln159 · FEDORA-2026-c593ef1d15 · source
sudo dnf upgrade --advisory=FEDORA-2026-c593ef1d15
Ubuntu 22.04 · firefox · NOT AFFECTED
Ubuntu 24.04 · firefox · NOT AFFECTED
Ubuntu 25.04 · firefox · NOT AFFECTED
Ubuntu 25.10 · firefox · NOT AFFECTED
Ubuntu 24.04 · thunderbird · NOT AFFECTED
Debian 12 · firefox-esr · FIXED · 140.4.0esr-1~deb12u1
sudo apt update && sudo apt install --only-upgrade firefox-esr
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' firefox-esr)" ge "140.4.0esr-1~deb12u1" && echo PATCHED || echo STILL-VULNERABLE
Debian 13 · firefox-esr · FIXED · 140.4.0esr-1~deb13u1
sudo apt update && sudo apt install --only-upgrade firefox-esr
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' firefox-esr)" ge "140.4.0esr-1~deb13u1" && echo PATCHED || echo STILL-VULNERABLE
Debian 12 · thunderbird · FIXED · 1:140.4.0esr-1~deb12u1
sudo apt update && sudo apt install --only-upgrade thunderbird
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' thunderbird)" ge "1:140.4.0esr-1~deb12u1" && echo PATCHED || echo STILL-VULNERABLE
Debian 13 · thunderbird · FIXED · 1:140.4.0esr-1~deb13u1
sudo apt update && sudo apt install --only-upgrade thunderbird
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' thunderbird)" ge "1:140.4.0esr-1~deb13u1" && echo PATCHED || echo STILL-VULNERABLE
RHEL 10 · firefox · FIXED · firefox-140.4.0-3.el10_0
sudo dnf upgrade --advisory=RHSA-2025:18154
rpm -q firefox
RHEL 10 · thunderbird · FIXED · thunderbird-140.4.0-2.el10_0
sudo dnf upgrade --advisory=RHSA-2025:18320
rpm -q thunderbird
RHEL 7 Extended Lifecycle Support · firefox · FIXED · firefox-140.4.0-4.el7_9
sudo dnf upgrade --advisory=RHSA-2025:19278
rpm -q firefox
RHEL 8 · firefox · FIXED · firefox-140.4.0-3.el8_10
sudo dnf upgrade --advisory=RHSA-2025:18285
rpm -q firefox
RHEL 8 · thunderbird · FIXED · thunderbird-140.4.0-2.el8_10
sudo dnf upgrade --advisory=RHSA-2025:18983
rpm -q thunderbird
sudo dnf update --advisory=ALAS2023-2025-1246
sudo yum update --advisory=ALAS2-2025-3052
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
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