NULL Pointer Dereference Affecting openssl package, versions [0,1.1.1k)


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
8.15% (95th percentile)

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  • Snyk IDSNYK-UNMANAGED-OPENSSL-2318609
  • published14 Dec 2021
  • disclosed25 Mar 2021
  • creditUnknown

Introduced: 25 Mar 2021

CVE-2021-3449  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

Upgrade openssl to version 1.1.1k or higher.

Overview

Affected versions of this package are vulnerable to NULL Pointer Dereference. An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).

References

CVSS Scores

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