Cloud Controller is vulnerable to denial of service via YAML parsing

published 2020-12-02 5y ago modified 2026-06-17 4mo ago also EUVD-2020-26591

cvss: 7.5; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits: 0; none known

CAPI (Cloud Controller) versions prior to 1.101.0 are vulnerable to a denial-of-service attack in which an unauthenticated malicious attacker can send specially-crafted YAML files to certain endpoints, causing the YAML parser to consume excessive CPU and RAM.

Patch / fix

fixed in 2

Cloud Foundry CAPI 1.101.0
Cloud Foundry CF Deployment 15.0.0

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Exploit prediction

1.15% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	7.8	AV:N/AC:L/Au:N/C:N/I:N/A:C

Affected products

Cloud Foundry CAPI
Cloud Foundry CF Deployment

Classification

Weakness

CWE-400 Uncontrolled Resource Consumption

References

cloudfoundry.org /blog/cve-2020-5423
vendor-advisory

Sources

CVE List CVE-2020-5423
NVD CVE-2020-5423

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