CVE-2020-25687
dnsmasq: heap-based buffer overflow with large memcpy in sort_rrset() when DNSSEC is enabled
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
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.
Se encontró un fallo en dnsmasq versiones anteriores a 2.83. Se detectó un desbordamiento del búfer en la región heap de la memoria en dnsmasq cuando DNSSEC está habilitado y antes de comprobar las entradas DNS recibidas. Este fallo permite a un atacante remoto, que puede crear respuestas DNS válidas, causar un desbordamiento en una memoria asignada a la pila. Este fallo es causado por una falta de comprobación de longitud en la función rfc1035.c:extract_name(), que podría ser abusado para hacer que el código ejecutar memcpy() con un tamaño negativo en sort_rrset() y causar un bloqueo en dnsmasq, resultando en una denegación de servicio. La mayor amenaza de esta vulnerabilidad es la disponibilidad del sistema
A flaw was found in dnsmasq. 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.
CVSS Scores
SSVC
- Decision:-
Timeline
- 2020-09-16 CVE Reserved
- 2021-01-19 CVE Published
- 2024-08-04 CVE Updated
- 2024-11-09 EPSS Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
- CWE-122: Heap-based Buffer Overflow
CAPEC
References (9)
URL | Tag | Source |
---|---|---|
https://lists.debian.org/debian-lts-announce/2021/03/msg00027.html | Mailing List | |
https://www.jsof-tech.com/disclosures/dnspooq | Third Party Advisory |
URL | Date | SRC |
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URL | Date | SRC |
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https://bugzilla.redhat.com/show_bug.cgi?id=1891568 | 2021-01-19 |
Affected Vendors, Products, and Versions
Vendor | Product | Version | Other | Status | ||||||
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Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
Thekelleys Search vendor "Thekelleys" | Dnsmasq Search vendor "Thekelleys" for product "Dnsmasq" | < 2.83 Search vendor "Thekelleys" for product "Dnsmasq" and version " < 2.83" | - |
Affected
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Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 32 Search vendor "Fedoraproject" for product "Fedora" and version "32" | - |
Affected
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Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 33 Search vendor "Fedoraproject" for product "Fedora" and version "33" | - |
Affected
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Debian Search vendor "Debian" | Debian Linux Search vendor "Debian" for product "Debian Linux" | 9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0" | - |
Affected
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Debian Search vendor "Debian" | Debian Linux Search vendor "Debian" for product "Debian Linux" | 10.0 Search vendor "Debian" for product "Debian Linux" and version "10.0" | - |
Affected
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