CVE-2021-3420 · cross-distro fix matrix

CVE-2021-3420: A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Affects 8 Linux releases across 10 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-3420 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

picolibc→ fixed in1.5-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y picolibc
```

Debian bookworm

Source: Debian Security Tracker

newlib→ fixed in3.3.0-1.3+deb12u1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y newlib
```
picolibc→ fixed in1.5-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y picolibc
```

Debian trixie

Source: Debian Security Tracker

newlib→ fixed in4.4.0.20231231-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y newlib
```
picolibc→ fixed in1.5-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y picolibc
```

Alpine v3.20

Source: Alpine secdb

newlib→ fixed in4.1.0-r0
```
apk update && apk add --upgrade newlib
```

Alpine v3.21

Source: Alpine secdb

newlib→ fixed in4.1.0-r0
```
apk update && apk add --upgrade newlib
```

Alpine edge

Source: Alpine secdb

newlib→ fixed in4.1.0-r0
```
apk update && apk add --upgrade newlib
```

Alpine v3.18

Source: Alpine secdb

newlib→ fixed in4.1.0-r0
```
apk update && apk add --upgrade newlib
```

Alpine v3.19

Source: Alpine secdb

newlib→ fixed in4.1.0-r0
```
apk update && apk add --upgrade newlib
```

Are YOU affected by CVE-2021-3420?

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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