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CVE-2021-23839 · cross-distro fix matrix

CVE-2021-23839: OpenSSL 1.0.2 supports SSLv2. If a client attempts to negotiate SSLv2 with a server that is configured to support both SSLv2 and more recent SSL and TLS versions then a check is made for a version rollback attack when unpadding an RSA signature. Clients that support SSL or TLS versions greater than

Affects 8 Linux releases across 9 (distro × package) combinations.

Fix per ecosystem

Each block below is a distro release where CVE-2021-23839 has a known fix. Run the listed command on that distro to remediate.

Debian bullseye

Source: Debian Security Tracker

  • openssl→ fixed in1.0.0d-1urgency: not yet assigned
    sudo apt-get install --only-upgrade -y openssl

Debian bookworm

Source: Debian Security Tracker

  • openssl→ fixed in1.0.0d-1urgency: not yet assigned
    sudo apt-get install --only-upgrade -y openssl

Debian trixie

Source: Debian Security Tracker

  • openssl→ fixed in1.0.0d-1urgency: not yet assigned
    sudo apt-get install --only-upgrade -y openssl

Alpine v3.20

Source: Alpine secdb

  • openssl→ fixed in1.1.1j-r0
    apk update && apk add --upgrade openssl

Alpine v3.21

Source: Alpine secdb

  • openssl→ fixed in1.1.1j-r0
    apk update && apk add --upgrade openssl

Alpine edge

Source: Alpine secdb

  • openssl→ fixed in1.1.1j-r0
    apk update && apk add --upgrade openssl

Alpine v3.18

Source: Alpine secdb

  • openssl→ fixed in1.1.1j-r0
    apk update && apk add --upgrade openssl
  • openssl1.1-compat→ fixed in1.1.1j-r0
    apk update && apk add --upgrade openssl1.1-compat

Alpine v3.19

Source: Alpine secdb

  • openssl→ fixed in1.1.1j-r0
    apk update && apk add --upgrade openssl
Are YOU affected by CVE-2021-23839?

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
Continuous monitoring beats manual checking

CVE-2021-23839dropped silently in your distro's update channel. Every new CVE is the same story. StackPatch runs the matcher hourly against all 5 sources and emails the exact remediation when something new applies to one of your servers. $99 lifetime, 50 founder seats, 30-day refund.

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