CyberSecBulletin
CVE-2026-40525NVD status: Analyzed

OpenViking: Not Failing Securely

CVE-2026-40525 is a critical-severity not failing securely vulnerability in OpenViking from Volcengine, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 0.3.9 as the first without the flaw, so updating OpenViking to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.59% 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. Update OpenViking to 0.3.9 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. 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
VolcengineOpenVikingbefore 0.3.90.3.9

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
NoneAvailability is not affected.

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

Scoring systemScoreSeverityScored by
CVSS 4.09.1CriticalCNA (vulncheck.com)
CVSS 3.19.1CriticalCNA (vulncheck.com)

Official description

OpenViking prior to version 0.3.9 contains an authentication bypass vulnerability in the VikingBot OpenAPI HTTP route surface where the authentication check fails open when the api_key configuration value is unset or empty. Remote attackers with network access to the exposed service can invoke privileged bot-control functionality without providing a valid X-API-Key header, including submitting attacker-controlled prompts, creating or using bot sessions, and accessing downstream tools, integrations, secrets, or data accessible to the bot.

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

The underlying weakness: Not Failing Securely

When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that are available, such as selecting the weakest encryption algorithm or using the most permissive access control restrictions.

How developers prevent this class of flaw

  • Subdivide and allocate resources and components so that a failure in one part does not affect the entire product.

More Not Failing Securely vulnerabilities (CWE-636)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in OpenViking

All OpenViking vulnerabilities

Recent Not Failing Securely vulnerabilities

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