CVE-2016-6515
What it is
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.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 58.6% chance of exploitation in the next 30 days (EPSS). Higher than most.
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 58.6% in the next 30 days (EPSS).
- Severity: 7.5 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 58.6% · EPSS, next 30 days
- Weakness
- CWE-20 · Improper input validation
- Record status
- Modified
Affected
- Openbsd OpenSSH ≤ 7.2
- Fedoraproject Fedora 24
Attack profile CVSS 3.0 · 7.5
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2016-6515.md and follow it. Check whether this project is affected by CVE-2016-6515. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://github.com/openssh/openssh-portable/commit/fcd135c9df440bcd2d5870405ad3311743d78d97
- https://github.com/openssh/openssh-portable/commit/fcd135c9df440bcd2d5870405ad3311743d78d97
References
- http://openwall.com/lists/oss-security/2016/08/01/2
- http://packetstormsecurity.com/files/140070/OpenSSH-7.2-Denial-Of-Service.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- http://www.securityfocus.com/bid/92212
- http://www.securitytracker.com/id/1036487
- https://access.redhat.com/errata/RHSA-2017:2029
- https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-676336.pdf
- https://github.com/openssh/openssh-portable/commit/fcd135c9df440bcd2d5870405ad3311743d78d97
- https://lists.debian.org/debian-lts-announce/2018/09/msg00010.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X2L6RW34VFNXYNVVN2CN73YAGJ5VMTFU/
- https://security.FreeBSD.org/advisories/FreeBSD-SA-17:06.openssh.asc
- https://security.netapp.com/advisory/ntap-20171130-0003/
- https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03779en_us
- https://www.exploit-db.com/exploits/40888/
- http://openwall.com/lists/oss-security/2016/08/01/2
- http://packetstormsecurity.com/files/140070/OpenSSH-7.2-Denial-Of-Service.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- http://www.securityfocus.com/bid/92212
- http://www.securitytracker.com/id/1036487
- https://access.redhat.com/errata/RHSA-2017:2029
- https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-676336.pdf
- https://github.com/openssh/openssh-portable/commit/fcd135c9df440bcd2d5870405ad3311743d78d97
- https://lists.debian.org/debian-lts-announce/2018/09/msg00010.html