CVE-2016-2181: openssl Numeric Errors
Vulnerability summary
CVE-2016-2181 is a high (CVSS 7.5) Numeric Errors vulnerability in openssl. EPSS estimates a 22.63% chance of exploitation in the next 30 days, higher than 97.7% of scored vulnerabilities.
Severe, CVSS 7.5 (NVD); no exploitation reported by the 5 checked sources; EPSS 23% (FIRST, 04-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 12 · Related 7Timeline
- 16-09-2016PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
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 metrics
5 scores · 4 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
22.63%
Chance of exploitation in the next 30 days
Percentile
98%
Versus all other CVEs
30-day change
No change 0.00 pp
From 22.63% on 05-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- openssl< 1.0.2h-r4
Debian1 product
- openssl< 1.0.2i-1
Openssl1 product
- opensslEOL1.0.1 | 1.0.1a | 1.0.1b | 1.0.1c | 1.0.1d | 1.0.1e | 1.0.1f | 1.0.1g | 1.0.1h | 1.0.1i | 1.0.1j | 1.0.1k | 1.0.1l | 1.0.1m | 1.0.1n | 1.0.1o | 1.0.1p | 1.0.1q | 1.0.1r | 1.0.1s | 1.0.1t | 1.0.2 | 1.0.2a | 1.0.2b | 1.0.2c | 1.0.2d | 1.0.2e | 1.0.2f | 1.0.2g | 1.0.2h
Oracle1 product
- linuxEOL6 | 7
Ubuntu1 product
- openssl< 1.0.1f-1ubuntu2.20 | < 1.0.2g-1ubuntu4.4
5 vendors · 5 products
References
47 links- www.splunk.com/view/SP-CAAAPUEThird Party Advisory
- rhn.redhat.com/errata/RHSA-2016-1940.htmlVendor Advisory
- www.oracle.com/technetwork/topics/security/linuxbulletinoct2016-3090545.htmlThird Party Advisory
- kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA40312Third Party Advisory
- www.splunk.com/view/SP-CAAAPSVThird Party Advisory
- www-01.ibm.com/support/docview.wss?uid=swg21995039Third Party Advisory
- www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.htmlThird Party Advisory
Show all 47 references
- www.tenable.com/security/tns-2016-16Third Party Advisory
- www.securitytracker.com/id/1036690VDB Entry
- www.oracle.com/technetwork/topics/security/ovmbulletinoct2016-3090547.htmlThird Party Advisory
- bto.bluecoat.com/security-advisory/sa132Third Party Advisory
- security.freebsd.org/advisories/FreeBSD-SA-16:26.openssl.ascVendor Advisory
- kb.juniper.net/InfoCenter/index?page=content&id=JSA10759Third Party Advisory
- www.ubuntu.com/usn/USN-3087-1Vendor Advisory
- www.ubuntu.com/usn/USN-3087-2Vendor Advisory
- seclists.org/fulldisclosure/2017/Jul/31Mailing List
www.debian.org/security/2016/dsa-3673Vendor Advisory