Red Hat Enterprise Linux 9 update for unbound
| Risk | Medium |
| Patch available | YES |
| Number of vulnerabilities | 2 |
| CVE-ID | CVE-2022-30698 CVE-2022-30699 |
| CWE-ID | CWE-341 |
| Exploitation vector | Network |
| Public exploit | N/A |
| Vulnerable software |
Red Hat Enterprise Linux for ARM 64 Operating systems & Components / Operating system Red Hat Enterprise Linux for Power, little endian Operating systems & Components / Operating system Red Hat Enterprise Linux for IBM z Systems Operating systems & Components / Operating system Red Hat Enterprise Linux for x86_64 Operating systems & Components / Operating system unbound (Red Hat package) Operating systems & Components / Operating system package or component |
| Vendor | Red Hat Inc. |
Security Bulletin
This security bulletin contains information about 2 vulnerabilities.
1) Predictable from Observable State
EUVDB-ID: #VU66548
Risk: Medium
CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2022-30698
CWE-ID:
CWE-341 - Predictable from Observable State
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to poison DNS cache.
The vulnerability exists due to the way Unbound handles delegation information expiration event. A remote attacker who controls a rouge DNS server can force the Unbound instance to cache incorrect information about subdomain delegation and permanently poison the DNS cache, e.g. perform the "ghost domain names" attack.
The attack is carried out when Unbound is queried for a subdomain of a rogue domain name. The rogue nameserver returns delegation information for the subdomain that updates Unbound's delegation cache. This action can be repeated before expiry of the delegation information by querying Unbound for a second level subdomain which the rogue nameserver provides new delegation information. Since Unbound is a child-centric resolver, the ever-updating child delegation information can keep a rogue domain name resolvable long after revocation. MitigationInstall updates from vendor's website.
Red Hat Enterprise Linux for ARM 64: 9
Red Hat Enterprise Linux for Power, little endian: 9
Red Hat Enterprise Linux for IBM z Systems: 9
Red Hat Enterprise Linux for x86_64: 9
unbound (Red Hat package): before 1.16.2-2.el9
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_arm_64:9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian:9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:red_hat_enterprise_linux:9:*:*:*:*:*:*:*
- cpe:2.3:o:red_hat:unbound_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHSA-2022:8062
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
2) Predictable from Observable State
EUVDB-ID: #VU66547
Risk: Medium
CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2022-30699
CWE-ID:
CWE-341 - Predictable from Observable State
Exploit availability: No
DescriptionThe vulnerability allows a remote attacker to poison DNS cache.
The vulnerability exists due to the way Unbound handles delegation information expiration event. A remote attacker who controls a rouge DNS server can force the Unbound instance to cache incorrect information about domain delegation and permanently poison the DNS cache, e.g. perform the "ghost domain names" attack.
The attack is perform when Unbound is queried for a rogue domain name, which cached delegation information is about to expire. The rogue nameserver delays the response until the cached delegation information expires. Upon receiving the delayed answer containing the delegation information, Unbound overwrites the now expired entries.
MitigationInstall updates from vendor's website.
Red Hat Enterprise Linux for ARM 64: 9
Red Hat Enterprise Linux for Power, little endian: 9
Red Hat Enterprise Linux for IBM z Systems: 9
Red Hat Enterprise Linux for x86_64: 9
unbound (Red Hat package): before 1.16.2-2.el9
CPE2.3- cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_arm_64:9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power_little_endian:9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:9:*:*:*:*:red_hat_enterprise_linux:*:*
- cpe:2.3:o:red_hat:red_hat_enterprise_linux:9:*:*:*:*:*:*:*
- cpe:2.3:o:red_hat:unbound_redhat_package:*:*:*:*:*:red_hat_enterprise_linux:*:*
https://access.redhat.com/errata/RHSA-2022:8062
Q & A
Can this vulnerability be exploited remotely?
Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
