Is CVE-2025-27809 in the CISA KEV catalog?

No. CVE-2025-27809 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2025-27809?

CVE-2025-27809 has a CVSS v3 base score of 5.4 (MEDIUM).

What is the EPSS score for CVE-2025-27809?

CVE-2025-27809 has an EPSS score of 0.18% (8th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2025-27809?

Upgrade mbedtls on debian 13 to 3.6.3-1 or later.

CVE & CISA-KEV Catalog

CVE-2025-27809

MEDIUM

5.4

CVSS v3

NVD

Description

Mbed TLS before 2.28.10 and 3.x before 3.6.3, on the client side, accepts servers that have trusted certificates for arbitrary hostnames unless the TLS client application calls mbedtls_ssl_set_hostname.

CWE-1188

How to fix

Remediation Available

mbedtlsDebian

Fixed in:3.6.3-1CVE-2025-27809

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeChanged

Impact

ConfidentialityLow

IntegrityLow

AvailabilityNone

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

Exploit Intelligence

0.18%probability of exploitation in 30 days

8thpercentile

Low risk: more likely to be exploited than 8% of all known CVEs.

References

Third-Party Advisory1

mbed-tls.readthedocs.io

Issue Tracking1

github.com

Release Notes1

github.com

Other references1

mastodon.social

Related Vulnerabilities

Other CWE-1188 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2020-13927	Critical	9.8	100%	KEV	Fix
CVE-2023-27524	High	8.9	97%	KEV	-
CVE-2022-24706	Critical	9.8	92%	KEV	Fix
CVE-2020-11532	Critical	9.8	77%	-	Fix
CVE-2018-16752	High	8.8	43%	-	-
CVE-2020-14011	Critical	9.8	29%	-	-

Embed a live status badge for CVE-2025-27809

Markdown

[![CVE-2025-27809](https://tridentstack.com/cve/badge/CVE-2025-27809.svg)](https://tridentstack.com/cve/CVE-2025-27809)

HTML

<a href="https://tridentstack.com/cve/CVE-2025-27809"><img src="https://tridentstack.com/cve/badge/CVE-2025-27809.svg" alt="CVE-2025-27809"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-05.