CVE-2020-24240 · cross-distro fix matrix

CVE-2020-24240: GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '\0' byte is encountered. NOTE: there is a risk only if Bison is used with untrusted input, and the observed bug happens to cause unsafe behavior with a specific compiler/architecture. The bug

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

Fix per ecosystem

Each block below is a distro release where CVE-2020-24240 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

bison→ fixed in2:3.7.2+dfsg-1urgency: unimportant
```
sudo apt-get install --only-upgrade -y bison
```

Debian bookworm

Source: Debian Security Tracker

bison→ fixed in2:3.7.2+dfsg-1urgency: unimportant
```
sudo apt-get install --only-upgrade -y bison
```

Debian trixie

Source: Debian Security Tracker

bison→ fixed in2:3.7.2+dfsg-1urgency: unimportant
```
sudo apt-get install --only-upgrade -y bison
```

Alpine v3.20

Source: Alpine secdb

bison→ fixed in3.7.2-r0
```
apk update && apk add --upgrade bison
```

Alpine v3.21

Source: Alpine secdb

bison→ fixed in3.7.2-r0
```
apk update && apk add --upgrade bison
```

Alpine edge

Source: Alpine secdb

bison→ fixed in3.7.2-r0
```
apk update && apk add --upgrade bison
```

Alpine v3.18

Source: Alpine secdb

bison→ fixed in3.7.2-r0
```
apk update && apk add --upgrade bison
```

Alpine v3.19

Source: Alpine secdb

bison→ fixed in3.7.2-r0
```
apk update && apk add --upgrade bison
```

Are YOU affected by CVE-2020-24240?

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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Continuous monitoring beats manual checking

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