Mobile token disclosure via hard-coded callback key
Published Aug 19, 2026 · Updated Aug 19, 2026
Improper callback registration in Splunk Secure Gateway before 3.10.10, 3.9.24, and 3.8.71 allows remote authenticated users to expose mobile tokens. The companion app registration handler uses a hard-coded cryptographic key to authorize registration and accepts arbitrary callback URLs, allowing a malicious companion app entry to redirect forwarded mobile requests to an attacker-controlled endpoint. Exploitation requires a Splunk account without the admin or power roles; the disclosed impact is theft of tokens and access to data reachable through the affected mobile user's session.
Summary
What happened
Improper callback registration in Splunk Secure Gateway before 3.10.10, 3.9.24, and 3.8.71 allows remote authenticated users to expose mobile tokens. The companion app registration handler uses a hard-coded cryptographic key to authorize registration and accepts arbitrary callback URLs, allowing a malicious companion app entry to redirect forwarded mobile requests to an attacker-controlled endpoint. Exploitation requires a Splunk account without the admin or power roles; the disclosed impact is theft of tokens and access to data reachable through the affected mobile user's session.
The record
- CVE
- CVE-2026-76258
- Published
- Aug 19, 2026
- Updated
- Aug 19, 2026
- Vendor
- Zoom Video Communications, Inc.
- Product
- Splunk Enterprise
- Classifications
- CWE-321, T1528
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 19, 2026CVE publishedPublication date reported by the CVE source.
- Aug 19, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0 <10.0.9
- Affected versionversion=10.2 <10.2.6
- Affected versionversion=10.4 <10.4.2
- Affected versionversion=9.4 <9.4.14
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo