High 7.5Published Sep 16, 2016

CVE-2016-2181The Anti-Replay feature in the DTLS implementation in OpenSSL before 1.1.0 mishandles early use of a new epoch number in conjunction with a large sequence number, which allows remote attackers to cau…

Updated under an hour ago (Nov 2, 2026, 12:10 AM ET)

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The Anti-Replay feature in the DTLS implementation in OpenSSL before 1.1.0 mishandles early use of a new epoch number in conjunction with a large sequence number, which allows remote attackers to cause a denial of service (false-positive packet drops) via spoofed DTLS records, related to rec_layer_d1.c and ssl3_record.c.

CVSS: 7.5 HIGH (v3.0, NVD)CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-189
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Modified
Record last updated: Jun 16, 2026
First seen by InfoSec Signals: Nov 1, 2026

Affected products

Affected products

openssl openssl openssl:openssl	1.0.1; 1.0.1a; 1.0.1b; 1.0.1c; 1.0.1d; 1.0.1e; 1.0.1f; 1.0.1g; and 22 more ranges	NVD
oracle linux oracle:linux	6; 7	NVD

References

References

http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759	third-party-advisory
http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00022.html
http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00023.html
http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00024.html
http://lists.opensuse.org/opensuse-security-announce/2016-09/msg00031.html
http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00005.html
http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00011.html
http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00012.html
http://lists.opensuse.org/opensuse-security-announce/2016-10/msg00029.html
http://lists.opensuse.org/opensuse-security-announce/2017-10/msg00010.html
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