How severe is CVE-2025-27377?

CVE-2025-27377 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2025-27377 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-27377?

CVE-2025-27377 affects Altium Designer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-27377?

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

Does CVE-2025-27377 have an EU (EUVD) identifier?

Yes. CVE-2025-27377 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4175.

When was CVE-2025-27377 published?

CVE-2025-27377 was published on 2026-01-22 and last updated on 2026-06-17.

CVE-2025-27377

CVE-2025-27377 is a medium-severity vulnerability in Altium Designer with a CVSS 3.x base score of 5.3. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-4175
Weakness: CWE-295
Affected product: Altium Designer
Published: 2026-01-22
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2025-27377?: 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.
How severe is CVE-2025-27377?: CVE-2025-27377 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2025-27377 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-27377?: CVE-2025-27377 affects Altium Designer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-27377?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-27377 have an EU (EUVD) identifier?: Yes. CVE-2025-27377 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4175.
When was CVE-2025-27377 published?: CVE-2025-27377 was published on 2026-01-22 and last updated on 2026-06-17.

References

https://www.altium.com/platform/security-compliance/security-advisories

Affected products (1)

cpe:2.3:a:altium:designer:*:*:*:*:*:*:*:*

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