krb5: krb5 may accept authdata checksums with low-entropy derived keys (MITKRB5-SA-2010-007)
Published Dec 2, 2010
6.3
MEDIUMCVSS 3.0
EPSS 1.92%
Description
MIT Kerberos 5 (aka krb5) 1.8.x through 1.8.3 does not reject RC4 key-derivation checksums, which might allow remote authenticated users to forge a (1) AD-SIGNEDPATH or (2) AD-KDC-ISSUED signature, and possibly gain privileges, by leveraging the small key space that results from certain one-byte stream-cipher operations.
Affected products
No data.
- 1.8
- 1.8.1
- 1.8.2
- 1.8.3
No data.
Red Hat Enterprise Linux 6
krb5-0:1.8.2-3.el6_0.3
Fixed · RHSA-2010:0925
Red Hat Enterprise Linux 5
krb5
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | krb5-0:1.8.2-3.el6_0.3 | Fixed | RHSA-2010:0925 |
| Red Hat Enterprise Linux 5 | krb5 | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue did not affect the versions of krb5 as shipped with Red Hat Enterprise Linux 3, 4 and 5.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
AV:N/AC:M/Au:S/C:N/I:P/A:N
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 (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.92% (0.01916) | 79.11th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.92% (0.01916) | 77.11th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.53% (0.00535) | 65.42th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.25% (0.00247) | 65.28th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.25% (0.00247) | 63.77th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.25% (0.00247) | 60.83th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.53% (0.02528) | 81.92th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.53% (0.02528) | 80.15th | v2 (v2022.01.01) |
| Feb 4, 2022 | 2.53% (0.02528) | 58.66th | v2 (v2022.01.01) |
References (27)
- http://kb.vmware.com/kb/1035108 x_refsource_CONFIRM
- http://lists.apple.com/archives/security-announce/2011/Mar/msg00006.html vendor-advisoryx_refsource_APPLE
- http://lists.fedoraproject.org/pipermail/package-announce/2010-December/051976.html vendor-advisoryx_refsource_FEDORA
- http://lists.fedoraproject.org/pipermail/package-announce/2010-December/051999.html vendor-advisoryx_refsource_FEDORA
- http://lists.opensuse.org/opensuse-security-announce/2010-12/msg00000.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2010-12/msg00006.html vendor-advisoryx_refsource_SUSE
- http://lists.vmware.com/pipermail/security-announce/2011/000133.html mailing-listx_refsource_MLIST
- http://osvdb.org/69608 vdb-entryx_refsource_OSVDB
- http://secunia.com/advisories/42399 third-party-advisoryx_refsource_SECUNIAVendor Advisory
- http://support.apple.com/kb/HT4581 x_refsource_CONFIRM
- http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2010-007.txt x_refsource_CONFIRMVendor Advisory
- http://www.mandriva.com/security/advisories?name=MDVSA-2010:246 vendor-advisoryx_refsource_MANDRIVA
- http://www.oracle.com/technetwork/topics/security/cpujul2015-2367936.html x_refsource_CONFIRMPatchVendor Advisory
- http://www.redhat.com/support/errata/RHSA-2010-0925.html vendor-advisoryx_refsource_REDHAT
- http://www.securityfocus.com/archive/1/514953/100/0/threaded mailing-listx_refsource_BUGTRAQ
- http://www.securityfocus.com/archive/1/517739/100/0/threaded mailing-listx_refsource_BUGTRAQ
- http://www.securityfocus.com/bid/45117 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id?1024803 vdb-entryx_refsource_SECTRACK
- http://www.ubuntu.com/usn/USN-1030-1 vendor-advisoryx_refsource_UBUNTU
- http://www.vmware.com/security/advisories/VMSA-2011-0007.html x_refsource_CONFIRM
- http://www.vupen.com/english/advisories/2010/3094 vdb-entryx_refsource_VUPEN
- http://www.vupen.com/english/advisories/2010/3095 vdb-entryx_refsource_VUPEN
- http://www.vupen.com/english/advisories/2010/3118 vdb-entryx_refsource_VUPEN
- https://access.redhat.com/security/cve/CVE-2010-4020 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=648735 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2010-4020
- https://www.cve.org/CVERecord?id=CVE-2010-4020
Change history (0)
No recorded changes yet.