CVE-2025-25234
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedOmnissa UAG contains a Cross-Origin Resource Sharing (CORS) bypass vulnerability. A malicious actor with network access to UAG may be able to bypass administrator-configured CORS restrictions to gain access to sensitive networks.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceOmnissa Unified Access Gateway (UAG) contains a CORS bypass vulnerability where an attacker with network access can circumvent administrator-configured Cross-Origin Resource Sharing policies, potentially allowing unauthorized cross-origin requests to sensitive network resources.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 2503CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check the installed UAG versionAccess the UAG admin interface and navigate to the Settings or About section to view the version number, or use the command line interface if available to query the installed versionAffected if The installed version is lower than 2503 (for example, 2409, 2406, or earlier)
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Confirm CORS policies are configuredIn the UAG admin interface, locate the Cross-Origin Resource Sharing (CORS) settings under the relevant network or proxy configuration section. Verify that any CORS allow rules or origin whitelists have been definedAffected if CORS policies have been configured by an administrator - the bypass only impacts environments with CORS restrictions in place
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Review the CORS configuration for allowed originsExamine the configured allowed origins, methods, and headers in the UAG CORS settings. Note which origins are whitelisted and whether wildcard origins (*) are in useAffected if Any CORS origin whitelist exists, as the bypass could allow attackers to circumvent these restrictions
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Verify network exposure of the UAG interfaceConfirm whether the UAG management or proxy interfaces are accessible from untrusted networks. Check firewall rules and access profiles that control who can reach the UAG endpointsAffected if The UAG is accessible from networks beyond the trusted internal environment, providing an attacker with the network access needed to exploit the CORS bypass
The environment is affected if UAG version is below 2503 AND CORS policies are configured AND the UAG is accessible from untrusted networks.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped2503
Apply the vendor-provided patch for CVE-2025-25234 to the UAG deployment and verify that administrator-configured CORS restrictions are properly enforced after the update.
2503 or later
- Obtain the Omnissa Unified Access Gateway version 2503 or later from the official Omnissa download portal at static.omnissa.com or www.omnissa.com
- Review the UAG upgrade documentation for version 2503
- Ensure you have a complete backup of the current UAG configuration
- Deploy the upgrade following the standard UAG upgrade procedure
- After upgrade, verify that CORS restrictions are functioning correctly by testing configured policies
- Confirm the UAG version is now 2503 or later
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,408.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-25234 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-25234 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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