CyberSecBulletin
CVE-2026-81032NVD status: Deferred

nebula: Missing Authentication for Critical Functionality

Published Updated By the CyberSecBulletin desk

CVE-2026-81032 is a critical-severity missing authentication for critical functionality vulnerability in nebula from Vesoft, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected nebula versions: 3.8.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of nebula you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Vesoft-incnebula3.8.0 and earlierNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.09.3CriticalCNA (vulncheck.com)
CVSS 3.19.8CriticalCNA (vulncheck.com)

Official description

NebulaGraph exposes its runtime configuration over an unauthenticated HTTP service. Each daemon starts the web service defined in src/webservice/WebService.cpp, whose bind address defaults to all interfaces, and registers routes for reading and writing gflags alongside status and statistics. Neither the service nor its router carries any authentication, token check or address restriction. The read route returns the daemon's full set of runtime flag values, which includes the configured certificate, key and certificate-authority paths, the password file path, data directories and the transport-security enable flags. The write route parses a supplied map and applies each entry through the gflags runtime setter, so a caller able to reach the port can change the daemon's behaviour without restarting it, including disabling the transport-security flags, redirecting log files and altering flags such as failed_login_attempts and password_lock_time_in_secs. Public reports of this endpoint describe a single name, enable_authorize, being refused by the handler; at release 3.8.0 that refusal is not present and the handler applies every name it is given.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Missing Authentication for Critical Functionality

The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
  • When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.

More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Missing Authentication for Critical Functionality vulnerabilities

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