A memory leak in the OCUtil.dll library used by Nextcloud Desktop Client 2.6.4 can lead to a DoS against the host system.

published 2020-08-10 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-29101

cvss: 5.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits: 0; none known

Patch / fix

fixed in 1

nextcloud desktop 2.6.5

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-8229 updated 2025-11-21 cvss 5.5

nextcloud: memory leak in the OCUtil.dll leads to DoS

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.47% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

hackerone.com https://hackerone.com/reports/588562 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	4.9	AV:L/AC:L/Au:N/C:N/I:N/A:C

Affected products

n/a Desktop Client

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption
CWE-401 Missing Release of Memory after Effective Lifetime

References

hackerone.com /reports/588562
exploit, third-party-advisory
nextcloud.com /security/advisory/?id=NC-SA-2020-034
broken-link, vendor-advisory

Sources

CVE List CVE-2020-8229
NVD CVE-2020-8229

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