Vulnerability · Published Nov 11, 2020 · Assigned by microsoft
CVE-2020-17049Kerberos KDC Security Feature Bypass Vulnerability
Medium 6.6
In plain English
A medium-severity security flaw in Windows Server 2008 R2 Service Pack 1 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 13.8% (higher than 97% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)6.6Medium
Exploit odds (30 days)13.8%top 3.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A security feature bypass vulnerability exists in the way Key Distribution Center (KDC) determines if a service ticket can be used for delegation via Kerberos Constrained Delegation (KCD). To exploit the vulnerability, a compromised service that is configured to use KCD could tamper with a service ticket that is not valid for delegation to force the KDC to accept it. The update addresses this vulnerability by changing how the KDC validates service tickets used with KCD.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | bind-dyndb-ldap | 11.6-4.module_el8.6.0+3339+9b5fdd22 | ALSA-2024:0143 |
| AlmaLinux:8 | custodia | 0.6.0-3.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-client | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-client-common | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-client-epn | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-client-samba | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-common | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-healthcheck | 0.12-3.module_el8.9.0+3651+d05ea4c5 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-healthcheck-core | 0.12-3.module_el8.9.0+3651+d05ea4c5 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-python-compat | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-selinux | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-server | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-server-common | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-server-dns | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | ipa-server-trust-ad | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:9 | krb5-devel | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:9 | krb5-libs | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:9 | krb5-pkinit | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:9 | krb5-server | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:9 | krb5-server-ldap | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:9 | krb5-workstation | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:9 | libkadm5 | 1.20.1-8.el9 | ALSA-2023:2570 |
| AlmaLinux:8 | opendnssec | 2.1.7-1.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | opendnssec | 2.1.7-1.module_el8.6.0+3031+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-custodia | 0.6.0-3.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-ipaclient | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-ipalib | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-ipaserver | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-ipatests | 4.9.12-11.module_el8.9.0+3715+e4197dc9.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-jwcrypto | 0.5.0-1.1.module_el8.7.0+3349+cfeff52e | ALSA-2024:0143 |
| AlmaLinux:8 | python3-kdcproxy | 0.4-5.module_el8.9.0+3682+f63caf3e | ALSA-2024:0143 |
| AlmaLinux:8 | python3-pyusb | 1.0.0-9.1.module_el8.7.0+3349+cfeff52e | ALSA-2024:0143 |
| AlmaLinux:8 | python3-qrcode | 5.1-12.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-qrcode-core | 5.1-12.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | python3-yubico | 1.3.2-9.1.module_el8.7.0+3349+cfeff52e | ALSA-2024:0143 |
| AlmaLinux:8 | slapi-nis | 0.60.0-4.module_el8.9.0+3682+f63caf3e.alma.1 | ALSA-2024:0143 |
| AlmaLinux:8 | softhsm | 2.6.0-5.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | softhsm | 2.6.0-5.module_el8.6.0+3031+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | softhsm-devel | 2.6.0-5.module_el8.6.0+2881+2f24dc92 | ALSA-2024:0143 |
| AlmaLinux:8 | softhsm-devel | 2.6.0-5.module_el8.6.0+3031+2f24dc92 | ALSA-2024:0143 |
| Rocky Linux:8 | custodia | 0:0.6.0-3.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |
| Rocky Linux:8 | ipa-healthcheck | 0:0.12-3.module+el8.9.0+1433+5bd2f890 | RLSA-2024:0143 |
| Rocky Linux:8 | ipa-healthcheck | 0:0.12-3.module+el8.9.0+1434+912e18bd | RLSA-2024:0143 |
| Rocky Linux:8 | opendnssec | 0:2.1.7-1.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |
| Rocky Linux:8 | python-kdcproxy | 0:0.4-5.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |
| Rocky Linux:8 | python-kdcproxy | 0:0.4-5.module+el8.10.0+1915+3c70f7d9.1 | RLSA-2024:0143 |
| Rocky Linux:8 | python-qrcode | 0:5.1-12.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |
| Rocky Linux:8 | python-qrcode | 0:5.1-12.module+el8.9.0+1372+09f67869 | RLSA-2024:0143 |
| Rocky Linux:8 | python-yubico | 0:1.3.2-9.1.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |
| Rocky Linux:8 | python-yubico | 0:1.3.2-9.1.module+el8.9.0+1372+09f67869 | RLSA-2024:0143 |
| Rocky Linux:8 | pyusb | 0:1.0.0-9.1.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |
| Rocky Linux:8 | pyusb | 0:1.0.0-9.1.module+el8.9.0+1372+09f67869 | RLSA-2024:0143 |
| Rocky Linux:8 | slapi-nis | 0:0.60.0-4.module+el8.9.0+1573+39ab85f4 | RLSA-2024:0143 |
| Rocky Linux:8 | softhsm | 0:2.6.0-5.module+el8.9.0+1371+ffa84eb9 | RLSA-2024:0143 |