What is CVE-2021-43171?

CVE-2021-43171 is a medium-severity vulnerability in E.foundation App Lounge, classified under Improper Verification of Cryptographic Signature. CVSS score: 6.5/10. Published 2023-08-22.

How severe is CVE-2021-43171?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in E.foundation App Lounge

CVE-2021-43171

Improper verification of applications' cryptographic signatures in the /e/OS app store client App Lounge before 0.19q allows attackers in control of the application server to install malicious applications on user's systems by altering the server's API response.

Published 2023-08-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (32.4th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 32nd percentile — 32.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

E.foundation App Lounge

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

nervuri.net/e/apps (Third Party Advisory)
gitlab.e.foundation/e/os/releases/-/releases/v0.19-q (Release Notes)

Frequently asked questions

What is CVE-2021-43171?: CVE-2021-43171 is a medium-severity vulnerability in E.foundation App Lounge, classified under Improper Verification of Cryptographic Signature. CVSS score: 6.5/10. Published 2023-08-22.
How severe is CVE-2021-43171?: Medium severity. CVSS v3 base score is 6.5 out of 10.