How severe is CVE-2025-66902?

CVE-2025-66902 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2025-66902 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66902?

CVE-2025-66902 affects Pithikos Websocket Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-66902?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-66902 have an EU (EUVD) identifier?

Yes. CVE-2025-66902 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3328.

When was CVE-2025-66902 published?

CVE-2025-66902 was published on 2026-01-20 and last updated on 2026-06-17.

CVE-2025-66902

CVE-2025-66902 is a high-severity vulnerability in Pithikos Websocket Server with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-3328
Weakness: CWE-20
Affected product: Pithikos Websocket Server
Published: 2026-01-20
Last modified: 2026-06-17

Description

An input validation issue in in Pithikos websocket-server v.0.6.4 allows a remote attacker to obtain sensitive information or cause unexpected server behavior via the websocket_server/websocket_server.py, WebSocketServer._message_received components.

Frequently asked questions

What is CVE-2025-66902?: An input validation issue in in Pithikos websocket-server v.0.6.4 allows a remote attacker to obtain sensitive information or cause unexpected server behavior via the websocket_server/websocket_server.py, WebSocketServer._message_received components.
How severe is CVE-2025-66902?: CVE-2025-66902 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2025-66902 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66902?: CVE-2025-66902 affects Pithikos Websocket Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-66902?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-66902 have an EU (EUVD) identifier?: Yes. CVE-2025-66902 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-3328.
When was CVE-2025-66902 published?: CVE-2025-66902 was published on 2026-01-20 and last updated on 2026-06-17.

References

https://github.com/cyberinvest211/websocket-server-vuln-poc/tree/main

Affected products (1)

cpe:2.3:a:pithikos:websocket_server:0.6.4:*:*:*:*:*:*:*

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