Fedora 31 update for pdns-recursor

1) Input validation error

EUVDB-ID: #VU28141

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-10995

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input when processing DNS responses. A remote attacker who controls a malicious DNS server can send a specially crafted response and perform a denial of service (DoS) attack against third-party DNS servers.

The attack is triggered by random subdomains in the NSDNAME in NS records.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

Fedora: 31

pdns-recursor: before 4.2.2-1.fc31

CPE2.3

• cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
• cpe:2.3:a:fedoraproject:pdns-recursor:*:*:*:*:*:fedora:*:*

External links

https://bodhi.fedoraproject.org/updates/FEDORA-2020-c0ff3df740

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) Input validation error

EUVDB-ID: #VU28142

Risk: Medium

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-12244

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a spoofing attack.

The vulnerability exists due to records in the answer section of a NXDOMAIN response lacking an SOA are not properly validated in SyncRes::processAnswer. A remote attacker with ability to perform a Man-in-the-Middle (MitM) attack can send a NXDOMAIN answer for a name that does exist and bypass DNSSEC validation.

Successful exploitation of the vulnerability may allow an attacker to perform a spoofing attack.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

Fedora: 31

pdns-recursor: before 4.2.2-1.fc31

CPE2.3

• cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
• cpe:2.3:a:fedoraproject:pdns-recursor:*:*:*:*:*:fedora:*:*

External links

https://bodhi.fedoraproject.org/updates/FEDORA-2020-c0ff3df740

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.

3) Out-of-bounds read

EUVDB-ID: #VU28143

Risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-10030

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition when processing a hostname via the gethostname()  function. A local user with ability to change system hostname can trigger out-of-bounds read error and read contents of memory on the system.

Mitigation

Install updates from vendor's repository.

Vulnerable software versions

Fedora: 31

pdns-recursor: before 4.2.2-1.fc31

CPE2.3

• cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
• cpe:2.3:a:fedoraproject:pdns-recursor:*:*:*:*:*:fedora:*:*

External links

https://bodhi.fedoraproject.org/updates/FEDORA-2020-c0ff3df740

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.