CVE-2025-40363 · cross-distro fix matrix

CVE-2025-40363: In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix field-spanning memcpy warning in AH output Fix field-spanning memcpy warnings in ah6_output() and ah6_output_done() where extension headers are copied to/from IPv6 address fields, triggering fortify-string warnings

Affects 3 Linux releases across 4 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2025-40363 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

linux→ fixed in5.10.247-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```
linux-6.1→ fixed in6.1.159-1~deb11u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux-6.1
```

Debian bookworm

Source: Debian Security Tracker

linux→ fixed in6.1.159-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Debian trixie

Source: Debian Security Tracker

linux→ fixed in6.12.63-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Are YOU affected by CVE-2025-40363?

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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