CVE-2019-3856 · cross-distro fix matrix

CVE-2019-3856: An integer overflow flaw, which could lead to an out of bounds write, was discovered in libssh2 before 1.8.1 in the way keyboard prompt requests are parsed. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server.

Affects 8 Linux releases across 8 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2019-3856 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libssh2→ fixed in1.8.0-2.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libssh2
```

Debian bookworm

Source: Debian Security Tracker

libssh2→ fixed in1.8.0-2.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libssh2
```

Debian trixie

Source: Debian Security Tracker

libssh2→ fixed in1.8.0-2.1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libssh2
```

Alpine v3.20

Source: Alpine secdb

libssh2→ fixed in1.8.1-r0
```
apk update && apk add --upgrade libssh2
```

Alpine v3.21

Source: Alpine secdb

libssh2→ fixed in1.8.1-r0
```
apk update && apk add --upgrade libssh2
```

Alpine edge

Source: Alpine secdb

libssh2→ fixed in1.8.1-r0
```
apk update && apk add --upgrade libssh2
```

Alpine v3.18

Source: Alpine secdb

libssh2→ fixed in1.8.1-r0
```
apk update && apk add --upgrade libssh2
```

Alpine v3.19

Source: Alpine secdb

libssh2→ fixed in1.8.1-r0
```
apk update && apk add --upgrade libssh2
```

Are YOU affected by CVE-2019-3856?

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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