Debian 11: net-snmp Important Buffer Overflow Fix DLA-4430-1 CVE-2025-68615

A specially crafted packet to an net-snmp snmptrapd daemon can cause a
buffer overflow and the daemon to crash.

(SNMP ports should never be open to public networks. There is no
mitigation available other than ensuring ports to snmptrapd are
appropriately firewalled or by upgrading.)

Additionally a problem with parsing /proc/net/snmp on Linux >= 6.7 (which
contains an additional OutTransmits field) was fixed.

For Debian 11 bullseye, this problem has been fixed in version
5.9+dfsg-4+deb11u3.

We recommend that you upgrade your net-snmp packages.

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

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://wiki.debian.org/LTS