Author Archives: anx

Does allowing binfmt_misc significantly increase the attack surface for unprivileged users that already can launch – native – binaries?

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The Linux kernel lets me register and execute additional binary formats as if they were regular executables.
I am thinking of this mostly as a convenience method, completing what specifying the interpreter via Shebang already partially acc… Continue reading Does allowing binfmt_misc significantly increase the attack surface for unprivileged users that already can launch – native – binaries?→

Does HTTP/3 necessitate additional – beyond HTTP/2 via TLS1.3 – restrictions on client authentication (mTLS)?

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A recent Nginx release allows me to set listen 443 quic; to enable HTTP/3. Neat. I had been using HTTP/2 with TLS1.3 before, so I did not expect that change much, just optimize round trips with otherwise matching security properties.
One m… Continue reading Does HTTP/3 necessitate additional – beyond HTTP/2 via TLS1.3 – restrictions on client authentication (mTLS)?→

Is gnupg2 –refresh-keys susceptible to any attacks based on fingerprint collisions?

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Alice updates her OpenPGP key yearly. Bob updates his copy using: gpg2 –refresh-keys

Mallory ensures that Bob uses her keyserver, which offers her own key, which

is sharing the 32-bit “short” Key ID with Alice
is sharing … Continue reading Is gnupg2 –refresh-keys susceptible to any attacks based on fingerprint collisions?→