Missing input validation on mod_auth_openidc_session_chunks cookie
value made the server vulnerable to this attack. If an attacker
manipulated the value of the OpenIDC cookie to a very large integer
like 99999999, the server struggled with the request for a long time
and finally returned a 500 error. Making a few requests of this kind
caused servers to become unresponsive, and so attackers could thereby
craft requests that would make the server work very hard and/or crash
with minimal effort.
For Debian 10 buster, this problem has been fixed in version
2.3.10.2-1+deb10u4.
We recommend that you upgrade your libapache2-mod-auth-openidc packages.
For the detailed security status of libapache2-mod-auth-openidc please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-package/libapache2-mod-auth-openidc
Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
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