9.8
CRITICAL
CVE-2021-45956
Dnsmasq Buffer Overflow Vulnerability
Description

Dnsmasq 2.86 has a heap-based buffer overflow in print_mac (called from log_packet and dhcp_reply). NOTE: the vendor's position is that CVE-2021-45951 through CVE-2021-45957 "do not represent real vulnerabilities, to the best of our knowledge.

INFO

Published Date :

Jan. 1, 2022, 12:15 a.m.

Last Modified :

Nov. 21, 2024, 6:33 a.m.

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2021-45956 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Thekelleys dnsmasq
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-45956.

URL Resource
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35887 Exploit Issue Tracking Third Party Advisory
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml Third Party Advisory
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html Mailing List Third Party Advisory
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html Mailing List Third Party Advisory
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35887 Exploit Issue Tracking Third Party Advisory
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml Third Party Advisory
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html Mailing List Third Party Advisory
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html Mailing List Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-45956 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-45956 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35887
    Added Reference https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml
    Added Reference https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html
    Added Reference https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Oct. 28, 2024

    Action Type Old Value New Value
    Added CWE CISA-ADP CWE-787
    Removed CWE CISA-ADP CWE-122
  • CVE Modified by [email protected]

    Aug. 04, 2024

    Action Type Old Value New Value
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 01, 2024

    Action Type Old Value New Value
    Added CWE CISA-ADP CWE-122
    Added CVSS V3.1 CISA-ADP AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • CVE Modified by [email protected]

    Jul. 18, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 17, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Apr. 11, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Mar. 21, 2024

    Action Type Old Value New Value
    Added Tag MITRE disputed
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Changed Description ** DISPUTED ** Dnsmasq 2.86 has a heap-based buffer overflow in print_mac (called from log_packet and dhcp_reply). NOTE: the vendor's position is that CVE-2021-45951 through CVE-2021-45957 "do not represent real vulnerabilities, to the best of our knowledge." Dnsmasq 2.86 has a heap-based buffer overflow in print_mac (called from log_packet and dhcp_reply). NOTE: the vendor's position is that CVE-2021-45951 through CVE-2021-45957 "do not represent real vulnerabilities, to the best of our knowledge.
  • Modified Analysis by [email protected]

    Mar. 18, 2022

    Action Type Old Value New Value
    Changed Reference Type https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml Exploit, Third Party Advisory https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml Third Party Advisory
    Changed Reference Type https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html No Types Assigned https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html Mailing List, Third Party Advisory
    Changed Reference Type https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html No Types Assigned https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html Mailing List, Third Party Advisory
  • CVE Modified by [email protected]

    Feb. 19, 2022

    Action Type Old Value New Value
    Changed Description Dnsmasq 2.86 has a heap-based buffer overflow in print_mac (called from log_packet and dhcp_reply). ** DISPUTED ** Dnsmasq 2.86 has a heap-based buffer overflow in print_mac (called from log_packet and dhcp_reply). NOTE: the vendor's position is that CVE-2021-45951 through CVE-2021-45957 "do not represent real vulnerabilities, to the best of our knowledge."
    Added Reference https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016164.html [No Types Assigned]
    Added Reference https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2022q1/016162.html [No Types Assigned]
  • Initial Analysis by [email protected]

    Jan. 11, 2022

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:P/I:P/A:P)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35887 No Types Assigned https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35887 Exploit, Issue Tracking, Third Party Advisory
    Changed Reference Type https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml No Types Assigned https://github.com/google/oss-fuzz-vulns/blob/main/vulns/dnsmasq/OSV-2021-933.yaml Exploit, Third Party Advisory
    Added CWE NIST CWE-787
    Added CPE Configuration OR *cpe:2.3:a:thekelleys:dnsmasq:2.86:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-45956 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-45956 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.19 }} -0.00%

score

0.56571

percentile

CVSS31 - Vulnerability Scoring System
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