CVE-2021-28965 · cross-distro fix matrix

CVE-2021-28965: The REXML gem before 3.2.5 in Ruby before 2.6.7, 2.7.x before 2.7.3, and 3.x before 3.0.1 does not properly address XML round-trip issues. An incorrect document can be produced after parsing and serializing.

Affects 6 Linux releases across 6 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-28965 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

ruby2.7→ fixed in2.7.3-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y ruby2.7
```

Alpine v3.20

Source: Alpine secdb

ruby→ fixed in2.7.3-r0
```
apk update && apk add --upgrade ruby
```

Alpine v3.21

Source: Alpine secdb

ruby→ fixed in2.7.3-r0
```
apk update && apk add --upgrade ruby
```

Alpine edge

Source: Alpine secdb

ruby→ fixed in2.7.3-r0
```
apk update && apk add --upgrade ruby
```

Alpine v3.18

Source: Alpine secdb

ruby→ fixed in2.7.3-r0
```
apk update && apk add --upgrade ruby
```

Alpine v3.19

Source: Alpine secdb

ruby→ fixed in2.7.3-r0
```
apk update && apk add --upgrade ruby
```

Are YOU affected by CVE-2021-28965?

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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