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CVE-2026-43964 · cross-distro fix matrix

CVE-2026-43964: Kamil Frankowicz discovered that Postfix incorrectly handled certain

Affects 4 Linux releases across 38 (distro × package) combinations. First disclosed: 2026-05-07.

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 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
  • postfix-pgsql→ fixed in3.8.6-1ubuntu0.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-pgsql
  • postfix-sqlite→ fixed in3.8.6-1ubuntu0.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-sqlite

Ubuntu questing

Source: Ubuntu USN

  • postfix→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix
  • postfix-cdb→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-cdb
  • postfix-doc→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-doc
  • postfix-ldap→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-ldap
  • postfix-lmdb→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-lmdb
  • postfix-mongodb→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-mongodb
  • postfix-mysql→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-mysql
  • postfix-pcre→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-pcre
  • postfix-pgsql→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-pgsql
  • postfix-sqlite→ fixed in3.10.2-1ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-sqlite

Ubuntu resolute

Source: Ubuntu USN

  • postfix→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix
  • postfix-cdb→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-cdb
  • postfix-doc→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-doc
  • postfix-ldap→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-ldap
  • postfix-lmdb→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-lmdb
  • postfix-mongodb→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-mongodb
  • postfix-mysql→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-mysql
  • postfix-pcre→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-pcre
  • postfix-pgsql→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-pgsql
  • postfix-sqlite→ fixed in3.10.6-4ubuntu2.1USN-8253-1
    sudo apt-get install --only-upgrade -y postfix-sqlite
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
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