Vulnerability Monitor

The vendors, products, and vulnerabilities you care about

CVE-2020-25687


A flaw was found in dnsmasq before version 2.83. A heap-based buffer overflow was discovered in dnsmasq when DNSSEC is enabled and before it validates the received DNS entries. This flaw allows a remote attacker, who can create valid DNS replies, to cause an overflow in a heap-allocated memory. This flaw is caused by the lack of length checks in rfc1035.c:extract_name(), which could be abused to make the code execute memcpy() with a negative size in sort_rrset() and cause a crash in dnsmasq, resulting in a denial of service. The highest threat from this vulnerability is to system availability.


Published

2021-01-20T17:15:13.060

Last Modified

2024-11-21T05:18:28.237

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 5.9 (MEDIUM)

CVSSv2 Vector

AV:N/AC:M/Au:N/C:N/I:N/A:C

  • Access Vector: NETWORK
  • Access Complexity: MEDIUM
  • Authentication: NONE
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: COMPLETE
Exploitability Score

8.6

Impact Score

6.9

Weaknesses
  • Type: Primary
    CWE-122

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Application thekelleys dnsmasq < 2.83 Yes
Operating System fedoraproject fedora 32 Yes
Operating System fedoraproject fedora 33 Yes
Operating System debian debian_linux 9.0 Yes
Operating System debian debian_linux 10.0 Yes

References