Improper access control in Nextcloud Social app version 0.3.1 allowed to read posts of any user.

published 2020-11-19 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-29146

cvss: 5.3; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

Exploit prediction

1.02% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

hackerone.com https://hackerone.com/reports/921717 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:P/I:N/A:N

Affected products

n/a Nextcloud Social

Classification

Weakness

CWE-284 Improper Access Control
CWE-863 Incorrect Authorization

References

hackerone.com /reports/921717
exploit, third-party-advisory
nextcloud.com /security/advisory/?id=NC-SA-2020-042
broken-link, product

Sources

CVE List CVE-2020-8278
NVD CVE-2020-8278

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary