CVE-2021-3537 · cross-distro fix matrix

CVE-2021-3537: A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery mode and post-validated, the flaw could be used to crash the application. The highest thr

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-3537 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

libxml2→ fixed in2.9.10+dfsg-6.6urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libxml2
```

Debian bookworm

Source: Debian Security Tracker

libxml2→ fixed in2.9.10+dfsg-6.6urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libxml2
```

Debian trixie

Source: Debian Security Tracker

libxml2→ fixed in2.9.10+dfsg-6.6urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y libxml2
```

Alpine v3.20

Source: Alpine secdb

libxml2→ fixed in2.9.11-r0
```
apk update && apk add --upgrade libxml2
```

Alpine v3.21

Source: Alpine secdb

libxml2→ fixed in2.9.11-r0
```
apk update && apk add --upgrade libxml2
```

Alpine edge

Source: Alpine secdb

libxml2→ fixed in2.9.11-r0
```
apk update && apk add --upgrade libxml2
```

Alpine v3.18

Source: Alpine secdb

libxml2→ fixed in2.9.11-r0
```
apk update && apk add --upgrade libxml2
```

Alpine v3.19

Source: Alpine secdb

libxml2→ fixed in2.9.11-r0
```
apk update && apk add --upgrade libxml2
```

Are YOU affected by CVE-2021-3537?

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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