SB2022101461 - openEuler update for dhcp 



SB2022101461 - openEuler update for dhcp

Published: October 14, 2022

Security Bulletin ID SB2022101461
Severity
Medium
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 75% Low 25%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 secuirty vulnerabilities.


1) Reachable Assertion (CVE-ID: CVE-2021-25215)

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

The vulnerability exists due to a reachable assertion when processing DNAME records. A remote attacker can force named to add the same RRset to the ANSWER section more than once, trigger an assertion failure and crash the service. Both authoritative and recursive servers are affected by this issue during zone transfers.


2) Reachable Assertion (CVE-ID: CVE-2021-25214)

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

The vulnerability exists due to a reachable assertion when pressing IXFR queries. An IXFR stream containing SOA records with an owner name other than the transferred zone's apex may cause the receiving named server to inadvertently remove the SOA record for the zone in question from the zone database. This leads to an assertion failure when the next SOA refresh query for that zone is made. When a vulnerable version of named receives a malformed IXFR triggering the flaw described above, the named process will terminate due to a failed assertion the next time the transferred secondary zone is refreshed.


3) Resource exhaustion (CVE-ID: CVE-2021-25219)

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

The vulnerability exists due to BIND does not properly control consumption of internal resources when processing lame cache. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.


4) Reliance on Reverse DNS Resolution for a Security-Critical Action (CVE-ID: CVE-2021-25220)

The vulnerability allows a remote attacker to poison DNS cache.

The vulnerability exists due to an error in DNS forwarder implementation. When using forwarders, bogus NS records supplied by, or via, those forwarders may be cached and used by named if it needs to recurse for any reason, causing it to obtain and pass on potentially incorrect answers. The cache could become poisoned with incorrect records leading to queries being made to the wrong servers, which might also result in false information being returned to clients.



Remediation

Install update from vendor's website.