How severe is CVE-2021-3899?

CVE-2021-3899 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-3899 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3899?

CVE-2021-3899 primarily affects Canonical Apport. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3899?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2021-3899 have an EU (EUVD) identifier?

Yes. CVE-2021-3899 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-27131.

When was CVE-2021-3899 published?

CVE-2021-3899 was published on 2024-06-03 and last updated on 2026-06-17.

CVE-2021-3899

CVE-2021-3899 is a high-severity vulnerability in Canonical Apport with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-367.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-27131
Weakness: CWE-367
Affected product: Canonical Apport
Published: 2024-06-03
Last modified: 2026-06-17

Description

There is a race condition in the 'replaced executable' detection that, with the correct local configuration, allow an attacker to execute arbitrary code as root.

Frequently asked questions

What is CVE-2021-3899?: There is a race condition in the 'replaced executable' detection that, with the correct local configuration, allow an attacker to execute arbitrary code as root.
How severe is CVE-2021-3899?: CVE-2021-3899 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-3899 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3899?: CVE-2021-3899 primarily affects Canonical Apport. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3899?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-3899 have an EU (EUVD) identifier?: Yes. CVE-2021-3899 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-27131.
When was CVE-2021-3899 published?: CVE-2021-3899 was published on 2024-06-03 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:canonical:apport:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:21.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:22.04:*:*:*:lts:*:*:*

More vulnerabilities in Canonical Apport

CVE-2021-25684 — High (CVSS 8.8): It was discovered that apport in data/apport did not properly open a report file to prevent hanging reads on a FIFO.
CVE-2021-25683 — High (CVSS 8.8): It was discovered that the get_starttime() function in data/apport did not properly parse the /proc/pid/stat file from…
CVE-2021-25682 — High (CVSS 8.8): It was discovered that the get_pid_info() function in data/apport did not properly parse the /proc/pid/status file from…
CVE-2022-1242 — High (CVSS 7.8): Apport can be tricked into connecting to arbitrary sockets as the root user
CVE-2023-1326 — High (CVSS 7.7): A privilege escalation attack was found in apport-cli 2.26.0 and earlier which is similar to CVE-2023-26604. If a…
CVE-2022-28653 — High (CVSS 7.5): Users can consume unlimited disk space in /var/crash

All CVEs affecting Canonical Apport →

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