CVE-2026-40194 · cross-distro fix matrix

CVE-2026-40194: phpseclib is a PHP secure communications library. Starting in 0.1.1 and prior to 3.0.51, 2.0.53, and 1.0.28, phpseclib\Net\SSH2::get_binary_packet() uses PHP's != operator to compare a received SSH packet HMAC against the locally computed HMAC. != on equal-length binary strings in PHP uses memcmp(),

Affects 2 Linux releases across 6 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2026-40194 has a known fix. Run the listed command on that distro to remediate.

Debian bookworm

Source: Debian Security Tracker

php-phpseclib→ fixed in2.0.42-1+deb12u4urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y php-phpseclib
```
php-phpseclib3→ fixed in3.0.19-1+deb12u5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y php-phpseclib3
```
phpseclib→ fixed in1.0.20-1+deb12u4urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y phpseclib
```

Debian trixie

Source: Debian Security Tracker

php-phpseclib→ fixed in2.0.48-3+deb13u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y php-phpseclib
```
php-phpseclib3→ fixed in3.0.43-2+deb13u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y php-phpseclib3
```
phpseclib→ fixed in1.0.23-6+deb13u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y phpseclib
```

Are YOU affected by CVE-2026-40194?

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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