python-kerberos: checkPassword() does not verify KDC authenticity
Published Aug 25, 2017
9.2
CRITICALCVSS 4.0
EPSS 2.39%
Description
The checkPassword function in python-kerberos does not authenticate the KDC it attempts to communicate with, which allows remote attackers to cause a denial of service (bad response), or have other unspecified impact by performing a man-in-the-middle attack.
Affected products
No data.
- n/a
No data.
Red Hat Enterprise Linux 5
python-kerberos
Affected
Red Hat Enterprise Linux 6
python-kerberos
Affected
Red Hat Enterprise Linux 7
python-kerberos
Affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | python-kerberos | Affected | n/a |
| Red Hat Enterprise Linux 6 | python-kerberos | Affected | n/a |
| Red Hat Enterprise Linux 7 | python-kerberos | Affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue affects the versions of python-kerberos as shipped with Red Hat Enterprise Linux 5, 6, and 7. Red Hat Product Security has rated this issue as having Moderate security impact. Additionally this issue is difficult to exploit in most common scenarios (due to the need for a valid Kerberos TGT)c For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
Metrics
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:M/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
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 (13 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.39% (0.02390) | 83.36th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.30% (0.02303) | 81.01th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.96% (0.00963) | 74.47th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.79% (0.02794) | 76.82th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.96% (0.00963) | 74.95th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.29% (0.00286) | 69.67th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.29% (0.00286) | 67.94th | v3 (v2023.03.01) |
| May 8, 2023 | 0.29% (0.00286) | 64.01th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.22% (0.00224) | 58.81th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.21% (0.01213) | 66.61th | v2 (v2022.01.01) |
| Feb 17, 2023 | 1.21% (0.01213) | 66.22th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.21% (0.01213) | 64.21th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.21% (0.01213) | 40.54th | v2 (v2022.01.01) |
References (14)
- http://www.openwall.com/lists/oss-security/2015/05/21/3 mailing-listx_refsource_MLISTMailing ListPatchThird Party Advisory
- http://www.securityfocus.com/bid/74760 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2015-3206 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1223802 x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory
- https://github.com/advisories/GHSA-mffc-9gx5-99g3 Advisory
- https://github.com/apple/ccs-pykerberos/commit/9cb61c93f9b24dd18a0a315f3df5445529c5c333
- https://github.com/apple/ccs-pykerberos/issues/31 x_refsource_CONFIRMIssue TrackingPatchThird Party Advisory
- https://github.com/pypa/advisory-database/tree/main/vulns/kerberos/PYSEC-2017-49.yaml
- https://github.com/pypa/advisory-database/tree/main/vulns/pykerberos/PYSEC-2017-66.yaml
- https://nvd.nist.gov/vuln/detail/CVE-2015-3206
- https://pypi.python.org/pypi/kerberos x_refsource_CONFIRMPatchVendor Advisory
- https://web.archive.org/web/20150910143429/https://trac.calendarserver.org/ticket/833
- https://web.archive.org/web/20200228090829/http://www.securityfocus.com/bid/74760
- https://www.cve.org/CVERecord?id=CVE-2015-3206
Change history (0)
No recorded changes yet.