CVE-2025-27377 | Missing Validation of Self-Signed Certificates in Altium Designer Allows Man-in-the-Middle Attacks

Altium Designer version 24.9.0 does not validate self-signed server certificates for cloud connections. An attacker capable of performing a man-in-the-middle (MITM) attack could exploit this issue to intercept or manipulate network traffic, potentially exposing authentication credentials or sensitive design data.

Published: 2026-01-22 Last update: 2026-02-26 Assigner: 4760f414-e1ae-4ff1-bdad-c7a9c3538b79 Source: 4760f414-e1ae-4ff1-bdad-c7a9c3538b79
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-27377 is rated Low Risk (23/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). 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-2025-27377

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 2026-01-22 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-27377

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/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:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.6 3.6 4760f414-e1ae-4ff1-bdad-c7a9c3538b79

Weakness enumeration for CVE-2025-27377

Affected software / configurations for CVE-2025-27377

Vendor Product Version Raw CPE
altium designer >= 24.9.0, < 25.2.0 cpe:2.3:a:altium:designer:*:*:*:*:*:*:*:*

References for CVE-2025-27377

cvelogic Threat Intelligence