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CVE-2021-26720

Published: Feb 17, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-59
NVD MITRE
7.8CVSSHIGH
EPSS Score
0.4%
Top 68.9%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

avahi-daemon-check-dns.sh in the Debian avahi package through 0.8-4 is executed as root via /etc/network/if-up.d/avahi-daemon, and allows a local attacker to cause a denial of service or create arbitrary empty files via a symlink attack on files under /run/avahi-daemon. NOTE: this only affects the packaging for Debian GNU/Linux (used indirectly by SUSE), not the upstream Avahi product.

CVSS Vector Breakdown

AV:LAC:LPR:LUI:NS:UC:HI:HA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-59

Affected Products

Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
Astra Linux Special Edition для «Эльбрус»ООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
AvahiThe Avahi Project
On-prem
Networking Infrastructure / dns-dhcp-ntp
РОСА ХРОМАО «НТЦ ИТ РОСА»
On-prem
Operating Systems / linux-distro
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
the avahi projectoss-projectNetworking Infrastructureaka avahi
ао «нтц ит роса»commercialRUOperating Systems
and 3 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://nvd.nist.gov/vuln/detail/CVE-2021-26720
nvd.nist.gov
https://security-tracker.debian.org/tracker/CVE-2021-26720
security-tracker.debian.org
https://wiki.astralinux.ru/astra-linux-se16-bulletin-20220829SE16
wiki.astralinux.ru
and 12 more references View all →

Timeline

Published
Feb 17, 2021
Last Updated
Nov 21, 2024

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