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Birthday attacks against TLS ciphers with 64bit (Sweet32)

Gangi Reddy 71 Reputation points
2021-07-22T15:54:22.563+00:00

How to disable below vulnerability for TLS1.2 in Windows 10?

QID: 38657
THREAT:
Legacy block ciphers having block size of 64 bits are vulnerable to a practical collision attack when used in CBC mode.
All versions of SSL/TLS
protocol support cipher suites which use DES, 3DES, IDEA or RC2 as the symmetric encryption cipher are affected.

IMPACT:
Remote attackers can obtain cleartext data via a birthday attack against a long-duration encrypted session.
SOLUTION:
Disable and stop using DES, 3DES, IDEA or RC2 ciphers.
More information can be found at Microsoft Windows TLS changes docs
(https://learn.microsoft.com/en-us/windows-server/security/tls/tls-schannel-ssp-changes-in-windows-10-and-windows-server) and Microsoft Transport
Layer Security (TLS) registry settings (https://learn.microsoft.com/en-us/windows-server/security/tls/tls-registry-settings)

RESULTS:
CIPHER KEY-EXCHANGE AUTHENTICATION MAC ENCRYPTION(KEY-STRENGTH) GRADE
TLSv1.2 WITH 64-BIT CBC CIPHERS IS
SUPPORTED
DES-CBC3-SHA RSA RSA SHA1 3DES(168) MEDIUM

Windows 10 Security
Windows 10 Security
Windows 10: A Microsoft operating system that runs on personal computers and tablets.Security: The precautions taken to guard against crime, attack, sabotage, espionage, or another threat.
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  1. KTC_Church 16 Reputation points
    2023-03-15T20:40:17.0033333+00:00

    Or use IIS Crypto to manage cipher suites: https://www.nartac.com/Products/IISCrypto/Download