CVE-2026-43964 · cross-distro fix matrix

CVE-2026-43964: USN-8253-1 fixed a vulnerability in Postfix. This update provides the

Affects 6 Linux releases across 50 (distro × package) combinations. First disclosed: 2026-05-04.

CVSS v3:LOW · 3.7(NVD-published)

Fix per ecosystem

Each block below is a distro release where CVE-2026-43964 has a known fix. Run the listed command on that distro to remediate.

Ubuntu bionic

Source: Ubuntu USN

postfix→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix
```
postfix-cdb→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-cdb
```
postfix-doc→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-doc
```
postfix-ldap→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-ldap
```
postfix-lmdb→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-lmdb
```
postfix-mysql→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-mysql
```
postfix-pcre→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pcre
```
postfix-pgsql→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pgsql
```
postfix-sqlite→ fixed in3.3.0-1ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-sqlite
```

Ubuntu focal

Source: Ubuntu USN

postfix→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix
```
postfix-cdb→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-cdb
```
postfix-doc→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-doc
```
postfix-ldap→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-ldap
```
postfix-lmdb→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-lmdb
```
postfix-mysql→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-mysql
```
postfix-pcre→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pcre
```
postfix-pgsql→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pgsql
```
postfix-sqlite→ fixed in3.4.13-0ubuntu1.4+esm1USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-sqlite
```

Ubuntu trusty

Source: Ubuntu USN

postfix→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix
```
postfix-cdb→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-cdb
```
postfix-dev→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-dev
```
postfix-doc→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-doc
```
postfix-ldap→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-ldap
```
postfix-mysql→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-mysql
```
postfix-pcre→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pcre
```
postfix-pgsql→ fixed in2.11.0-1ubuntu1.2+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pgsql
```

Ubuntu xenial

Source: Ubuntu USN

postfix→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix
```
postfix-cdb→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-cdb
```
postfix-dev→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-dev
```
postfix-doc→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-doc
```
postfix-ldap→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-ldap
```
postfix-mysql→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-mysql
```
postfix-pcre→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pcre
```
postfix-pgsql→ fixed in3.1.0-3ubuntu0.4+esm4USN-8253-2
```
sudo apt-get install --only-upgrade -y postfix-pgsql
```

Ubuntu jammy

Source: Ubuntu USN

postfix→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix

postfix-cdb→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-cdb

postfix-doc→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-doc

postfix-ldap→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-ldap

postfix-lmdb→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-lmdb

postfix-mysql→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-mysql

postfix-pcre→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-pcre

postfix-pgsql→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-pgsql

postfix-sqlite→ fixed in3.6.4-1ubuntu1.4USN-8253-1

sudo apt-get install --only-upgrade -y postfix-sqlite

Ubuntu noble

Source: Ubuntu USN

postfix→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix

postfix-cdb→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix-cdb

postfix-doc→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix-doc

postfix-ldap→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix-ldap

postfix-lmdb→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix-lmdb

postfix-mysql→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix-mysql

postfix-pcre→ fixed in3.8.6-1ubuntu0.1USN-8253-1

sudo apt-get install --only-upgrade -y postfix-pcre

Are YOU affected by CVE-2026-43964?

5-second check on your actual server. Reads /etc/os-release, uname -r, and the distro's package manager; matches against this same cross-source index live.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan View on NVD

Continuous monitoring beats manual checking

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