The auth_password function in auth-passwd.c in sshd in OpenSSH before 7.3 does not limit password lengths for password authentication, which allows remote attackers to cause a denial of service (crypt CPU consumption) via a long string.
CVE-2016-6515
Score elevated to 8.3 because EPSS predicts 59% probability of exploitation within the next 30 days (top 1.0% of all CVEs). NVD baseline CVSS 7.5 retained for reference. Confidence: see factors.
- 767 internet-exposed hosts are running an affected version right now
- High exploitation likelihood — EPSS 59%
A fix is available — apply it.
767 internet-exposed hosts are running an affected version of CVE-2016-6515 right now.
EchelonGraph is the only CVE feed that fuses live vulnerability intelligence with its own live internet-exposure radar — so you see not just that a CVE is exploited, but how much of the internet is exposed to it right now.
- CVSS v3
- 7.5
- EG Score
- 8.3(high)
- EG Risk
- 65(Track)EG Risk 65/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity83% × 45%Exploitation59% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS
- 99.0%
- KEV
- Not listed
Published
August 7, 2016
Last Modified
May 6, 2026
References (30)
- cve@mitrehttp://openwall.com/lists/oss-security/2016/08/01/2
- cve@mitrehttp://packetstormsecurity.com/files/140070/OpenSSH-7.2-Denial-Of-Service.html
- cve@mitrehttp://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- cve@mitrehttp://www.securityfocus.com/bid/92212
- cve@mitrehttp://www.securitytracker.com/id/1036487
- cve@mitrehttps://access.redhat.com/errata/RHSA-2017:2029
- cve@mitrehttps://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
- cve@mitrehttps://cert-portal.siemens.com/productcert/pdf/ssa-676336.pdf
- cve@mitrehttps://github.com/openssh/openssh-portable/commit/fcd135c9df440bcd2d5870405ad3311743d78d97
- cve@mitrehttps://lists.debian.org/debian-lts-announce/2018/09/msg00010.html
- cve@mitrehttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X2L6RW34VFNXYNVVN2CN73YAGJ5VMTFU/
- cve@mitrehttps://security.FreeBSD.org/advisories/FreeBSD-SA-17:06.openssh.asc
- cve@mitrehttps://security.netapp.com/advisory/ntap-20171130-0003/
- cve@mitrehttps://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03779en_us
- cve@mitrehttps://www.exploit-db.com/exploits/40888/
Patch Availability(2)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | ssh-krb5 (1:7.2p2-4ubuntu2.1) @ xenial | 2026-05-22 | ubuntu |
| redhat | openssh-0:7.4p1-11.el7 | 2017-08-01 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
All Vendor Advisories
(2)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
Data Freshness Timeline
(refreshed 10× in last 7d / 27× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-24 14:13 UTCEPSS rescore
- 2026-07-23 14:15 UTCEPSS rescore
- 2026-07-23 01:23 UTCEG score recompute▲ 0.80
- 2026-07-22 22:03 UTCEG score recompute
- 2026-07-22 14:04 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-20 17:04 UTCEPSS rescore
- 2026-07-19 02:26 UTCEPSS rescore
- 2026-07-19 02:26 UTCEPSS rescore
- 2026-07-16 16:59 UTCEPSS rescore
- 2026-07-16 16:59 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 01:56 UTCEPSS rescore
- 2026-07-13 22:26 UTCEPSS rescore
- 2026-07-13 06:09 UTCEPSS rescore
- 2026-07-12 08:08 UTCOSV refresh
- 2026-07-11 08:24 UTCEPSS rescore
- 2026-07-08 15:10 UTCEPSS rescore
- 2026-07-05 02:27 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-28 04:53 UTCEPSS rescore
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- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-25 13:47 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-23 21:30 UTCEPSS rescore
- 2026-06-23 13:30 UTCOSV refresh
- 2026-06-22 14:23 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-19 19:23 UTCEPSS rescore
- 2026-06-19 19:23 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-17 17:50 UTCEPSS rescore
- 2026-06-17 17:50 UTCEPSS rescore
- 2026-06-16 17:50 UTCEPSS rescore
- 2026-06-15 17:45 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-12 23:09 UTCEPSS rescore
- 2026-06-11 13:57 UTCEPSS rescore
- 2026-06-08 14:14 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-06 15:59 UTCOSV refresh
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-04 13:10 UTCEPSS rescore
- 2026-06-04 13:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-27 13:38 UTCEPSS rescore
- 2026-05-27 13:38 UTCEPSS rescore
- 2026-05-26 07:17 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 19:05 UTCEG score recompute
- 2026-05-22 19:05 UTCVendor advisory
- 2026-05-22 19:05 UTCGHSA enrichment
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
Publicly available exploits
(2 references)Working exploit code is in the public domain (1 GitHub PoC) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- GitHub PoCopsxcq/exploit-CVE-2016-6515First seen Dec 9, 2016
OpenSSH remote DOS exploit and vulnerable container
Open source ↗ - Exploit-DBEDB-40888First seen Dec 7, 2016
OpenSSH 7.2 - Denial of Service
Open source ↗
Frequently asked(5)
What is CVE-2016-6515?
When was CVE-2016-6515 disclosed?
Is CVE-2016-6515 actively exploited?
What is the CVSS score of CVE-2016-6515?
How do I remediate CVE-2016-6515?
Dependency Blast Radius
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