CVE-2021-22947 · cross-distro fix matrix

CVE-2021-22947: When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upgrade to TLS security, the server can respond and send back multiple responses at once that curl caches. curl would then upgrade to TLS but not flush the in-queue of cached responses but instead

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

Fix per ecosystem

Each block below is a distro release where CVE-2021-22947 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

curl→ fixed in7.74.0-1.3+deb11u2urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y curl
```

Debian bookworm

Source: Debian Security Tracker

curl→ fixed in7.79.1-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y curl
```

Debian trixie

Source: Debian Security Tracker

curl→ fixed in7.79.1-1urgency: not yet assigned
```
sudo apt-get install --only-upgrade -y curl
```

Alpine v3.20

Source: Alpine secdb

curl→ fixed in7.79.0-r0
```
apk update && apk add --upgrade curl
```

Alpine v3.21

Source: Alpine secdb

curl→ fixed in7.79.0-r0
```
apk update && apk add --upgrade curl
```

Alpine edge

Source: Alpine secdb

curl→ fixed in7.79.0-r0
```
apk update && apk add --upgrade curl
```

Alpine v3.18

Source: Alpine secdb

curl→ fixed in7.79.0-r0
```
apk update && apk add --upgrade curl
```

Alpine v3.19

Source: Alpine secdb

curl→ fixed in7.79.0-r0
```
apk update && apk add --upgrade curl
```

Are YOU affected by CVE-2021-22947?

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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