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Fencer Vulns
medium 5.3

CVE-2025-27377 json

Missing Validation of Self-Signed Certificates in Altium Designer Allows Man-in-the-Middle Attacks

published 2026-01-22 9 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-4175

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits
0
none known

Summary

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.

Patch / fix

  • Altium Altium Designer 25.2

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
9 mo ago

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N

Affected products

  • Altium Altium Designer

Classification

Weakness
  • CWE-295 Improper Certificate Validation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.