OpenVPN version 2.4.0 suffers from an unauthenticated denial of service vulnerability.
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Ubuntu Security Notice 3284-1 - It was discovered that OpenVPN improperly triggered an assert when receiving an oversized control packet in some situations. A remote attacker could use this to cause a denial of service. It was discovered that OpenVPN improperly triggered an assert when packet ids rolled over. An authenticated remote attacker could use this to cause a denial of service. Various other issues were also addressed.
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