krb5: KDC hang when using LDAP backend caused by special principal name (MITKRB5-SA-2011-002)
Published Feb 10, 2011
5.0
MEDIUMCVSS 2.0
EPSS 4.20%
Description
The unparse implementation in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) 1.6.x through 1.9, when an LDAP backend is used, allows remote attackers to cause a denial of service (file descriptor exhaustion and daemon hang) via a principal name that triggers use of a backslash escape sequence, as demonstrated by a \n sequence.
Affected products
No data.
- 5-1.6.3
- 1.6
- 1.6.1
- 1.6.2
- 1.7
- 1.7.1
- 1.8
- 1.8.1
- 1.8.2
- 1.8.3
- 1.9
No data.
Red Hat Enterprise Linux 5
krb5-0:1.6.1-55.el5_6.1
Fixed · RHSA-2011:0199
Red Hat Enterprise Linux 6
krb5-0:1.8.2-3.el6_0.4
Fixed · RHSA-2011:0200
Red Hat Enterprise Linux 4
krb5
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | krb5-0:1.6.1-55.el5_6.1 | Fixed | RHSA-2011:0199 |
| Red Hat Enterprise Linux 6 | krb5-0:1.8.2-3.el6_0.4 | Fixed | RHSA-2011:0200 |
| Red Hat Enterprise Linux 4 | 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 or 4 as they did not include support for the LDAP backend.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:N/I:N/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 (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 4.20% (0.04202) | 90.65th | v5 (v2026.06.15) |
| Jun 15, 2026 | 4.20% (0.04202) | 89.63th | v5 (v2026.06.15) |
| Jan 18, 2026 | 10.75% (0.10754) | 93.11th | v4 (v2025.03.14) |
| Nov 9, 2025 | 12.61% (0.12614) | 93.66th | v4 (v2025.03.14) |
| Mar 30, 2025 | 11.07% (0.11071) | 92.82th | v4 (v2025.03.14) |
| Mar 29, 2025 | 18.99% (0.18990) | 92.31th | v4 (v2025.03.14) |
| Mar 17, 2025 | 11.07% (0.11071) | 92.93th | v4 (v2025.03.14) |
| Dec 12, 2024 | 2.85% (0.02851) | 91.08th | v3 (v2023.03.01) |
| Mar 7, 2023 | 2.85% (0.02851) | 89.13th | v3 (v2023.03.01) |
| Mar 6, 2023 | 4.36% (0.04358) | 88.02th | v2 (v2022.01.01) |
| Apr 1, 2022 | 4.36% (0.04358) | 86.83th | v2 (v2022.01.01) |
| Feb 4, 2022 | 4.36% (0.04358) | 70.59th | v2 (v2022.01.01) |
References (26)
- http://lists.opensuse.org/opensuse-security-announce/2011-02/msg00004.html vendor-advisoryx_refsource_SUSE
- http://mailman.mit.edu/pipermail/kerberos/2010-December/016800.html mailing-listx_refsource_MLIST
- http://secunia.com/advisories/43260 third-party-advisoryx_refsource_SECUNIAVendor Advisory
- http://secunia.com/advisories/43273 third-party-advisoryx_refsource_SECUNIAVendor Advisory
- http://secunia.com/advisories/43275 third-party-advisoryx_refsource_SECUNIAVendor Advisory
- http://secunia.com/advisories/46397 third-party-advisoryx_refsource_SECUNIA
- http://securityreason.com/securityalert/8073 third-party-advisoryx_refsource_SREASON
- http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2011-002.txt x_refsource_CONFIRMVendor Advisory
- http://www.mandriva.com/security/advisories?name=MDVSA-2011:024 vendor-advisoryx_refsource_MANDRIVA
- http://www.mandriva.com/security/advisories?name=MDVSA-2011:025 vendor-advisoryx_refsource_MANDRIVA
- http://www.redhat.com/support/errata/RHSA-2011-0199.html vendor-advisoryx_refsource_REDHAT
- http://www.redhat.com/support/errata/RHSA-2011-0200.html vendor-advisoryx_refsource_REDHAT
- http://www.securityfocus.com/archive/1/516299/100/0/threaded mailing-listx_refsource_BUGTRAQ
- http://www.securityfocus.com/archive/1/520102/100/0/threaded mailing-listx_refsource_BUGTRAQ
- http://www.securityfocus.com/bid/46265 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id?1025037 vdb-entryx_refsource_SECTRACK
- http://www.vmware.com/security/advisories/VMSA-2011-0012.html x_refsource_CONFIRM
- http://www.vupen.com/english/advisories/2011/0330 vdb-entryx_refsource_VUPENVendor Advisory
- http://www.vupen.com/english/advisories/2011/0333 vdb-entryx_refsource_VUPENVendor Advisory
- http://www.vupen.com/english/advisories/2011/0347 vdb-entryx_refsource_VUPENVendor Advisory
- http://www.vupen.com/english/advisories/2011/0464 vdb-entryx_refsource_VUPEN
- https://access.redhat.com/security/cve/CVE-2011-0281 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=668719 Issue Tracking
- https://exchange.xforce.ibmcloud.com/vulnerabilities/65324 vdb-entryx_refsource_XF
- https://nvd.nist.gov/vuln/detail/CVE-2011-0281
- https://www.cve.org/CVERecord?id=CVE-2011-0281
Change history (0)
No recorded changes yet.