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.

Published: 2025-03-25 Last update: 2026-06-05 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-27809 is rated Low Risk (33.3/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.14%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-27809

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-05 0.16% 0.14% -0.02%
2 2026-05-03 0.06% 0.16% +0.10%
3 2025-12-09 — 0.06% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-27809

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 2.7 [email protected]

Weakness enumeration for CVE-2025-27809

OS Trackers for CVE-2025-27809

vendor priority summary link
alpine — CVE-2025-27809: 2 source package rows (mbedtls, mbedtls2); 89 state rows across 10 repos (3.18-main, 3.19-main, 3.20-main, 3.21-community, 3.21-main, 3.22-community, 3.22-main, 3.23-community, edge-community, edge-main); fixed 10, open 79. https://security.alpinelinux.org/vuln/CVE-2025-27809
debian not yet assigned CVE-2025-27809 not yet assigned priority: Debian including 1 source packages (mbedtls), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2025-27809
ubuntu medium CVE-2025-27809 medium priority: Ubuntu including 1 source packages (mbedtls), 9 status rows across 9 suites (bionic, focal, jammy, noble, oracular, plucky, questing, upstream, xenial): ignored 7, needed 1, released 1. https://ubuntu.com/security/CVE-2025-27809

Affected software / configurations for CVE-2025-27809

Vendor Product Version Raw CPE
arm mbed_tls < 2.28.10 cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*
trustedfirmware mbed_tls >= 3.0.0, < 3.6.3 cpe:2.3:a:trustedfirmware:mbed_tls:*:*:*:*:*:*:*:*

References for CVE-2025-27809

cvelogic Threat Intelligence