CVE-2026-77092 Overview
CVE-2026-77092 is a deserialization of untrusted data vulnerability [CWE-502] in the Commvault Content Extractor component. The flaw affects privilege management within the Commvault data protection platform. A local, authenticated attacker with low privileges can supply crafted serialized data to the Content Extractor, leading to compromise of confidentiality, integrity, and availability on the affected host. Commvault addressed the issue in a maintenance release and instructs customers to update the Content Extractor. The vulnerability requires local access and specific attack conditions, which raises exploitation complexity.
Critical Impact
Successful exploitation allows a low-privileged local user to abuse insecure deserialization in the Commvault Content Extractor to escalate privileges and fully compromise the host's confidentiality, integrity, and availability.
Affected Products
- Commvault Commvault (Content Extractor component)
- All maintenance releases prior to the fixed version referenced in Commvault Security Advisory CV_2026_07_6
- Deployments where the Content Extractor processes attacker-controllable serialized inputs
Discovery Timeline
- 2026-09-08 - CVE-2026-77092 published to the National Vulnerability Database (NVD)
- 2026-09-11 - Last updated in NVD database
Technical Details for CVE-2026-77092
Vulnerability Analysis
The Commvault Content Extractor deserializes untrusted data without adequate validation of the object stream. During processing, the component reconstructs objects from serialized input that an authenticated local user can influence. This behavior falls under [CWE-502] Deserialization of Untrusted Data.
Because the Content Extractor operates within a privileged execution context, unsafe object reconstruction crosses a trust boundary. An attacker can supply a crafted payload that triggers gadget chains during deserialization, yielding code execution or privilege escalation within Commvault. The impact spans confidentiality, integrity, and availability of the host.
Exploitation is constrained by the local attack vector and the presence of specific preconditions in the target environment. The advisory characterizes the issue as a privilege management flaw, indicating that successful exploitation elevates the attacker beyond their assigned role.
Root Cause
The root cause is the acceptance and reconstruction of serialized objects from an untrusted source without type filtering, allow-listing, or cryptographic integrity checks. Deserialization operations invoke object initialization logic that attackers can weaponize using gadget chains present in the runtime.
Attack Vector
An authenticated local user with low privileges delivers a crafted serialized payload to a code path handled by the Content Extractor. When the component deserializes the payload, it triggers unintended method invocations that lead to privilege escalation and code execution under the Commvault service context. Network-based exploitation is not required.
No public proof-of-concept exploit is available at this time, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. See the Commvault Security Advisory CV_2026_07_6 for vendor-specific technical guidance.
Detection Methods for CVE-2026-77092
Indicators of Compromise
- Unexpected child processes spawned by Commvault Content Extractor service accounts, particularly shells or scripting interpreters.
- Serialized object files or temporary payloads written to Commvault working directories by non-administrative users.
- Anomalous privilege escalation events where a low-privileged local account transitions to Commvault service privileges.
- Crashes or exception traces referencing deserialization routines in Commvault application logs.
Detection Strategies
- Monitor Commvault application and audit logs for deserialization exceptions and abnormal object handling errors in the Content Extractor.
- Alert on process-lineage anomalies where the Content Extractor spawns interactive or administrative tooling.
- Baseline expected file writes to Commvault content processing directories and flag deviations from that baseline.
Monitoring Recommendations
- Enable verbose logging on the Content Extractor and forward events to a centralized SIEM or data lake for correlation.
- Track local logon activity for accounts that interact with Commvault components and alert on privilege changes.
- Correlate endpoint telemetry with Commvault audit trails to identify multi-step local escalation sequences.
How to Mitigate CVE-2026-77092
Immediate Actions Required
- Identify all Commvault deployments running the affected Content Extractor component and confirm the installed maintenance release.
- Apply the fixed maintenance release referenced in Commvault Security Advisory CV_2026_07_6 as soon as feasible.
- Restrict local interactive access on Commvault servers to the minimum set of administrators required for operations.
- Review recent privilege escalation events and Content Extractor logs for signs of prior exploitation attempts.
Patch Information
Commvault has released a resolved maintenance update that remediates the deserialization flaw in the Content Extractor. Customers should upgrade to the fixed release identified in the vendor advisory. Full remediation details are provided in the Commvault Security Advisory CV_2026_07_6.
Workarounds
- Enforce least-privilege on local accounts on Commvault hosts and remove unnecessary interactive logon rights.
- Isolate Commvault infrastructure on hardened management networks with strict jump-host access controls.
- Where operationally acceptable, disable or restrict Content Extractor features that process externally sourced serialized data until patching is complete.
- Increase monitoring of Commvault service account behavior until remediation is verified across the estate.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.