CVE-2025-27809
published 2025-03-25CVE-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…
PriorityP428medium5.4CVSS 3.1
AVNACHPRNUINSCCLILAN
EPSS
0.18%
8.2th percentile
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.
Affected
9 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| arm | mbed_tls | < 2.28.10 | 2.28.10 |
| debian | mbedtls | < mbedtls 3.6.3-1 (forky) | mbedtls 3.6.3-1 (forky) |
| mbed | mbedtls | < 2.28.10 | 2.28.10 |
| mbed | mbedtls | >= 0 < 3.6.3-1 | 3.6.3-1 |
| mbed | mbedtls | >= 0 < 3.6.3-1 | 3.6.3-1 |
| mbed | mbedtls | >= 3.0.0 < 3.6.3 | 3.6.3 |
| msrc | azl3_qemu_8.2.0-16_on_azure_linux_3.0 | — | — |
| msrc | cbl2_qemu_6.2.0-24_on_cbl_mariner_2.0 | — | — |
| trustedfirmware | mbed_tls | >= 3.0.0 < 3.6.3 | 3.6.3 |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
osv5.4MEDIUM
vendor_debian5.4MEDIUM
vendor_msrc5.4MEDIUM
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Microsoft
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_hostnam
vendor_msrc·2025-03-11·CVSS 5.4
CVE-2025-27809 [MEDIUM] CWE-1188 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_hostnam
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.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update t
Debian
CVE-2025-27809: mbedtls - Mbed TLS before 2.28.10 and 3.x before 3.6.3, on the client side, accepts server...
vendor_debian·2025·CVSS 5.4
CVE-2025-27809 [MEDIUM] CVE-2025-27809: mbedtls - Mbed TLS before 2.28.10 and 3.x before 3.6.3, on the client side, accepts server...
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.
Scope: local
bookworm: open
bullseye: open
forky: resolved (fixed in 3.6.3-1)
sid: resolved (fixed in 3.6.3-1)
trixie: resolved (fixed in 3.6.3-1)
GHSA
GHSA-76fv-m4gp-q47j: Mbed TLS before 2
ghsa_unreviewed·2025-03-25
CVE-2025-27809 [MEDIUM] CWE-1188 GHSA-76fv-m4gp-q47j: Mbed TLS before 2
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.
OSV
CVE-2025-27809: Mbed TLS before 2
osv·2025-03-25·CVSS 5.4
CVE-2025-27809 [MEDIUM] CVE-2025-27809: Mbed TLS before 2
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-03-25
Published