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CVE-2021-3939

Free of static data in accountsservice

Published: Nov 17, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-590
NVD MITRE
7.8CVSSHIGH
EPSS Score
0.3%
Top 74.4%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

Description

Ubuntu-specific modifications to accountsservice (in patch file debian/patches/0010-set-language.patch) caused the fallback_locale variable, pointing to static storage, to be freed, in the user_change_language_authorized_cb function. This is reachable via the SetLanguage dbus function. This is fixed in versions 0.6.55-0ubuntu12~20.04.5, 0.6.55-0ubuntu13.3, 0.6.55-0ubuntu14.1.

CVSS Vector Breakdown

AV:LAC:HPR:LUI:NS:CC:HI:HA:H
Exploitability
AV:LAttack Vector
Local
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-590CWE-763

Affected Products

accountsserviceUbuntu
On-prem
Operating Systems / linux-distro
accountsservicecanonical
On-prem
Operating Systems / linux-distro
ubuntu linuxcanonical
On-premOS
Operating Systems / linux-distro
UbuntuCanonical Ltd.
On-premOS
Operating Systems / linux-distro
ubuntucommercialGBOperating Systemsaka ubuntu linux
canonicalcommercialGBOperating Systemsaka canonical ltd.
canonical ltd.commercialGBOperating Systemsaka canonical

Attack Graph

Products CVE Techniques Tactics

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Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Privilege Escalation
View detailed technique mapping

References

https://ubuntu.com/security/notices/USN-5149-1
ubuntu.com
https://bugs.launchpad.net/ubuntu/+source/accountsservice/+bug/1950149
bugs.launchpad.net
http://packetstormsecurity.com/files/172848/Ubuntu-accountsservice-Double-Free-Memory-Corruption.html
packetstormsecurity.com
and 2 more references View all →

Timeline

Published
Nov 17, 2021
Last Updated
Nov 21, 2024

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