openssh: Privilege separation weakness related to PAM support
Published Aug 24, 2015
6.4
MEDIUMCVSS 3.1
EPSS 0.38%
Description
The monitor component in sshd in OpenSSH before 7.0 on non-OpenBSD platforms accepts extraneous username data in MONITOR_REQ_PAM_INIT_CTX requests, which allows local users to conduct impersonation attacks by leveraging any SSH login access in conjunction with control of the sshd uid to send a crafted MONITOR_REQ_PWNAM request, related to monitor.c and monitor_wrap.c.
Affected products
No data.
No data.
Red Hat Enterprise Linux 6
openssh-0:5.3p1-117.el6
Fixed · RHSA-2016:0741
Red Hat Enterprise Linux 7
openssh-0:6.6.1p1-22.el7
Fixed · RHSA-2015:2088
Red Hat Enterprise Linux 4
openssh
Will not fix
Red Hat Enterprise Linux 5
openssh
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | openssh-0:5.3p1-117.el6 | Fixed | RHSA-2016:0741 |
| Red Hat Enterprise Linux 7 | openssh-0:6.6.1p1-22.el7 | Fixed | RHSA-2015:2088 |
| Red Hat Enterprise Linux 4 | openssh | Will not fix | n/a |
| Red Hat Enterprise Linux 5 | openssh | Will not fix | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
AV:L/AC:M/Au:N/C:N/I:P/A:N
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed May 27, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.38% (0.00381) | 29.71th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.38% (0.00378) | 29.39th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.15% (0.00151) | 32.35th | v4 (v2025.03.14) |
| Mar 29, 2025 | 3.10% (0.03104) | 77.91th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.15% (0.00147) | 32.56th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.04% (0.00044) | 11.89th | v3 (v2023.03.01) |
| Jul 2, 2024 | 0.04% (0.00044) | 10.25th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00044) | 8.24th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.55% (0.01547) | 74.98th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.55% (0.01547) | 74.94th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.55% (0.01547) | 72.92th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.55% (0.01547) | 51.82th | v2 (v2022.01.01) |
References (22)
- http://lists.apple.com/archives/security-announce/2015/Oct/msg00005.html vendor-advisory
- http://lists.fedoraproject.org/pipermail/package-announce/2015-August/165170.html vendor-advisory
- http://lists.opensuse.org/opensuse-security-announce/2015-09/msg00017.html vendor-advisory
- http://rhn.redhat.com/errata/RHSA-2016-0741.html vendor-advisory
- http://seclists.org/fulldisclosure/2015/Aug/54 mailing-list
- http://www.openssh.com/txt/release-7.0 Vendor Advisory
- http://www.openwall.com/lists/oss-security/2015/08/22/1 mailing-list
- http://www.oracle.com/technetwork/topics/security/bulletinjan2016-2867206.html
- http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
- http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
- http://www.securityfocus.com/bid/76317 vdb-entry
- https://access.redhat.com/security/cve/CVE-2015-6563 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1252844 Issue Tracking
- https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
- https://github.com/openssh/openssh-portable/commit/d4697fe9a28dab7255c60433e4dd23cf7fce8a8b
- https://lists.debian.org/debian-lts-announce/2018/09/msg00010.html mailing-list
- https://nvd.nist.gov/vuln/detail/CVE-2015-6563
- https://security.gentoo.org/glsa/201512-04 vendor-advisory
- https://security.netapp.com/advisory/ntap-20180201-0002/
- https://support.apple.com/HT205375
- https://www.broadcom.com/support/fibre-channel-networking/security-advisories/brocade-security-advisory-2019-766
- https://www.cve.org/CVERecord?id=CVE-2015-6563
Change history (0)
No recorded changes yet.