CVE-2009-3639 · cross-distro fix matrix

CVE-2009-3639: The mod_tls module in ProFTPD before 1.3.2b, and 1.3.3 before 1.3.3rc2, when the dNSNameRequired TLS option is enabled, does not properly handle a '\0' character in a domain name in the Subject Alternative Name field of an X.509 client certificate, which allows remote attackers to bypass intended cl

Affects 3 Linux releases across 3 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2009-3639 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

proftpd-dfsg→ fixed in1.3.2a-2urgency: low

sudo apt-get install --only-upgrade -y proftpd-dfsg

Debian bookworm

Source: Debian Security Tracker

proftpd-dfsg→ fixed in1.3.2a-2urgency: low

sudo apt-get install --only-upgrade -y proftpd-dfsg

Debian trixie

Source: Debian Security Tracker

proftpd-dfsg→ fixed in1.3.2a-2urgency: low

sudo apt-get install --only-upgrade -y proftpd-dfsg

Are YOU affected by CVE-2009-3639?

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