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openssl-src NULL pointer Dereference in signature_algorithms processing

Moderate severity GitHub Reviewed Published Aug 25, 2021 to the GitHub Advisory Database • Updated Sep 5, 2023

Package

cargo openssl-src (Rust)

Affected versions

< 111.15.0

Patched versions

111.15.0

Description

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

Published by the National Vulnerability Database Mar 25, 2021
Reviewed Aug 19, 2021
Published to the GitHub Advisory Database Aug 25, 2021
Last updated Sep 5, 2023

Severity

Moderate
5.9
/ 10

CVSS base metrics

Attack vector
Network
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses

CVE ID

CVE-2021-3449

GHSA ID

GHSA-83mx-573x-5rw9

Credits

Checking history
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