Debian: DSA-5056-1 StrongSwan DoS Risk and Authentication Error

When using EAP authentication (RFC 3748), the successful completion of the
authentication is indicated by an EAP-Success message sent by the server to the
client. strongSwan's EAP client code handled early EAP-Success messages
incorrectly, either crashing the IKE daemon or concluding the EAP method
prematurely.

End result depend on the used configuration, more details can be found in
upstream advisory at
https://www.strongswan.org/blog/2022/01/24/strongswan-vulnerability-).html

For the oldstable distribution (buster), this problem has been fixed
in version 5.7.2-1+deb10u2.

For the stable distribution (bullseye), this problem has been fixed in
version 5.9.1-1+deb11u2.

We recommend that you upgrade your strongswan packages.

For the detailed security status of strongswan please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-package/strongswan

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