5.9

CVE-2021-22895: debian debian_linux Improper Certificate Validation

CVSS: 5.9v3.1MediumModified
AliasesUBUNTU-CVE-2021-22895DEBIAN-CVE-2021-22895
Published 11-06-2021Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-22895 is a medium (CVSS 5.9) Improper Certificate Validation vulnerability in debian debian_linux. EPSS estimates a 1.04% chance of exploitation in the next 30 days, higher than 63.3% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
34/100
0100
Medium · default modelHow is this calculated?
CVSS score
5.9/10
010
Medium · v3.1 (NVD)
EPSS score
1.04%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 2
DSA-4974-1MGASA-2021-0421

Timeline

  1. 11-06-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

Nextcloud Desktop Client before 3.3.1 is vulnerable to improper certificate validation due to lack of SSL certificate verification when using the "Register with a Provider" flow.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

1.04%

Chance of exploitation in the next 30 days

Percentile

63%

Versus all other CVEs

30-day change

0.00 pp

From 1.03% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.04%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (hackerone.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Debian2 products
Nextcloud1 product
Ubuntu1 product
  • nextcloud-desktopAll versions (No fix recorded)

3 vendors · 4 products

References

9 links