CVE-2021-4203 · cross-distro fix matrix

CVE-2021-4203: A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privileges may crash the system or leak internal kernel information.

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-4203 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

linux→ fixed in5.10.84-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Debian bookworm

Source: Debian Security Tracker

linux→ fixed in5.14.12-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Debian trixie

Source: Debian Security Tracker

linux→ fixed in5.14.12-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y linux
```

Are YOU affected by CVE-2021-4203?

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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