Re: FreeBSD Security Advisory FreeBSD-SA-21:07.openssl

On Fri, Mar 26, 2021 at 12:05:23AM +0000, FreeBSD Security Advisories wrote:
> A TLSv1.2 renegotiation ClientHello message sent to a TLS server that omits
> the signature_algorithms extension (where it was present in the initial
> ClientHello), but includes a signature_algorithms_cert extension results in a
> NULL pointer dereference in the server. [CVE-2021-3449]
> 
> III. Impact
> 
> The X509_V_FLAG_X509_STRICT issue can result in a bypass of the check that
> non-CA certificates must not be able to issue other certificates.
> 
> The renegotiation issue can result in a crash and a denial of service attack.

Hey all,

Has anyone looked at if/how setting map_at_zero=1 impacts the null ptr
deref issue?

Thanks,

-- 
Shawn Webb
Cofounder / Security Engineer
HardenedBSD

https://git.hardenedbsd.org/hardenedbsd/pubkeys/-/raw/master/Shawn_Webb/03A4CBEBB82EA5A67D9F3853FF2E67A277F8E1FA.pub.asc

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