CVE-2021-32556 | apport get_modified_conffiles() function command injection

It was discovered that the get_modified_conffiles() function in backends/packaging-apt-dpkg.py allowed injecting modified package names in a manner that would confuse the dpkg(1) call.

Published: 2021-06-12 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-32556 is rated Low Risk (25.2/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.13%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-32556

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 0.16% 0.13% -0.03%
2 2025-03-29 0.13% 0.16% +0.03%
3 2025-03-17 — 0.13% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-32556

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.8 3.1 LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.0 1.4 [email protected]
3.3 3.1 LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 1.8 1.4 [email protected]
2.1 2.0 LOW
AV:L/AC:L/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 3.9 2.9 [email protected]

Weakness enumeration for CVE-2021-32556

OS Trackers for CVE-2021-32556

vendor priority summary link
ubuntu medium CVE-2021-32556 medium priority: Ubuntu including 1 source packages (apport), 9 status rows across 9 suites (bionic, focal, groovy, hirsute, impish, jammy, trusty, upstream, xenial): released 8, needs-triage 1. https://ubuntu.com/security/CVE-2021-32556

Affected software / configurations for CVE-2021-32556

Vendor Product Version Raw CPE
canonical apport >= 2.14.1-0ubuntu3, < 2.14.1-0ubuntu3.29\+esm7 cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*
canonical apport >= 2.20.1, < 2.20.1-0ubuntu2.30\+esm1 cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*
canonical apport >= 2.20.9, < 2.20.9-0ubuntu7.24 cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*
canonical apport >= 2.20.11-0ubuntu27, < 2.20.11-0ubuntu27.18 cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*
canonical apport >= 2.20.11-0ubuntu50, < 2.20.11-0ubuntu50.7 cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*
canonical apport >= 2.20.11-0ubuntu65, < 2.20.11-0ubuntu65.1 cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*

References for CVE-2021-32556

cvelogic Threat Intelligence