CVE-2020-12403 · cross-distro fix matrix

CVE-2020-12403: A flaw was found in the way CHACHA20-POLY1305 was implemented in NSS in versions before 3.55. When using multi-part Chacha20, it could cause out-of-bounds reads. This issue was fixed by explicitly disabling multi-part ChaCha20 (which was not functioning correctly) and strictly enforcing tag length.

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

Fix per ecosystem

Each block below is a distro release where CVE-2020-12403 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

nss→ fixed in2:3.55-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y nss
```

Debian bookworm

Source: Debian Security Tracker

nss→ fixed in2:3.55-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y nss
```

Debian trixie

Source: Debian Security Tracker

nss→ fixed in2:3.55-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y nss
```

Alpine v3.20

Source: Alpine secdb

nss→ fixed in3.55-r0
```
apk update && apk add --upgrade nss
```

Alpine v3.21

Source: Alpine secdb

nss→ fixed in3.55-r0
```
apk update && apk add --upgrade nss
```

Alpine edge

Source: Alpine secdb

nss→ fixed in3.55-r0
```
apk update && apk add --upgrade nss
```

Alpine v3.18

Source: Alpine secdb

nss→ fixed in3.55-r0
```
apk update && apk add --upgrade nss
```

Alpine v3.19

Source: Alpine secdb

nss→ fixed in3.55-r0
```
apk update && apk add --upgrade nss
```

Are YOU affected by CVE-2020-12403?

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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