CVE-2025-5994 · cross-distro fix matrix

CVE-2025-5994: A multi-vendor cache poisoning vulnerability named 'Rebirthday Attack' has been discovered in caching resolvers that support EDNS Client Subnet (ECS). Unbound is also vulnerable when compiled with ECS support, i.e., '--enable-subnet', AND configured to send ECS information along with queries to upst

Affects 7 Linux releases across 7 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2025-5994 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

unbound→ fixed in1.13.1-1+deb11u5urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y unbound
```

Debian bookworm

Source: Debian Security Tracker

unbound→ fixed in1.17.1-2+deb12u3urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y unbound
```

Debian trixie

Source: Debian Security Tracker

unbound→ fixed in1.22.0-2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y unbound
```

Alpine v3.20

Source: Alpine secdb

unbound→ fixed in1.20.0-r2
```
apk update && apk add --upgrade unbound
```

Alpine v3.21

Source: Alpine secdb

unbound→ fixed in1.22.0-r1
```
apk update && apk add --upgrade unbound
```

Alpine edge

Source: Alpine secdb

unbound→ fixed in1.23.1-r0
```
apk update && apk add --upgrade unbound
```

Alpine v3.19

Source: Alpine secdb

unbound→ fixed in1.20.0-r2
```
apk update && apk add --upgrade unbound
```

Are YOU affected by CVE-2025-5994?

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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