CVE-2026-25793

Nebula is a scalable overlay networking tool. In versions from 1.7.0 to 1.10.2, when using P256 certificates (which is not the default configuration), it is possible to evade a blocklist entry created against the fingerprint of a certificate by using ECDSA Signature Malleability to use a copy of the certificate with a different fingerprint. This issue has been patched in version 1.10.3.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21	Patch
https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:slack:nebula:*:*:*:*:*:*:*:*

History

18 Feb 2026, 17:47

Type	Values Removed	Values Added
References	~~() https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21 -~~	() https://github.com/slackhq/nebula/commit/f573e8a26695278f9d71587390fbfe0d0933aa21 - Patch
References	~~() https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962 -~~	() https://github.com/slackhq/nebula/security/advisories/GHSA-69x3-g4r3-p962 - Vendor Advisory
First Time		Slack Slack nebula
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.1
CPE		cpe:2.3:a:slack:nebula::::::::

06 Feb 2026, 23:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-06 23:15

Updated : 2026-02-18 17:47

NVD link : CVE-2026-25793

Mitre link : CVE-2026-25793

CVE.ORG link : CVE-2026-25793

JSON object : View

Products Affected

slack

nebula

CWE

CWE-347

Improper Verification of Cryptographic Signature

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