Free of static data in accountsservice

published 2021-11-17 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-27152

cvss: 7.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 31%
public exploits: 0; none known

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.

Patch / fix

fixed in 1 distros 1

Ubuntu accountsservice 0.6.55-0ubuntu12~20.04.5, 0.6.55-0ubuntu13.3, 0.6.55-0ubuntu14.1

accountsservice Ubuntu 20.04 LTS 0.6.55-0ubuntu12~20.04.5
accountsservice Ubuntu 22.04 LTS 0.6.55-3ubuntu2

ubuntu advisories UBUNTU-CVE-2021-3939

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Exploit prediction

0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	7.8	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.2	AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

Ubuntu accountsservice

Classification

Weakness

CWE-590 Free of Memory not on the Heap
CWE-763 Release of Invalid Pointer or Reference

References

Sources

CVE List CVE-2021-3939
NVD CVE-2021-3939

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Summary