How severe is CVE-2025-27809?

CVE-2025-27809 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-27809 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-27809?

CVE-2025-27809 primarily affects Arm Mbed Tls. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-27809?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-27809 have an EU (EUVD) identifier?

Yes. CVE-2025-27809 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-8055.

When was CVE-2025-27809 published?

CVE-2025-27809 was published on 2025-03-25 and last updated on 2026-06-17.

CVE-2025-27809

CVE-2025-27809 is a medium-severity vulnerability in Arm Mbed Tls with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1188.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-8055
Weakness: CWE-1188
Affected product: Arm Mbed Tls
Published: 2025-03-25
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-27809?: 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.
How severe is CVE-2025-27809?: CVE-2025-27809 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-27809 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-27809?: CVE-2025-27809 primarily affects Arm Mbed Tls. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-27809?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-27809 have an EU (EUVD) identifier?: Yes. CVE-2025-27809 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-8055.
When was CVE-2025-27809 published?: CVE-2025-27809 was published on 2025-03-25 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*
cpe:2.3:a:trustedfirmware:mbed_tls:*:*:*:*:*:*:*:*

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