# CVE-2026-77101: Commvault CommServe stack-based buffer overflow

Source: https://junglewise.ai/threats/cve-2026-77101-commvault-commserve-stack-based-buffer-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-08. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-77101 · Severity: high · CVSS 7.5 · Published 2026-09-08

Commvault CommServe is the core backup and data management platform used to protect enterprise data. A stack-based buffer overflow vulnerability allows an attacker to crash the service or potentially execute code, disrupting backup operations and data protection across an organization.

Technologies: [Commvault CommServe](https://junglewise.ai/threats/technologies/commserve). Vendors: [Commvault](https://junglewise.ai/threats/vendors/commvault).

## Quick answers

**Is CVE-2026-77101 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77101 being exploited in the wild.

**How severe is CVE-2026-77101?** High severity, with a CVSS score of 7.5, published 8 September 2026.

**Which products and versions are affected?** Commvault CommServe 11.36.0–11.36.122, 11.40.0–11.40.71, 11.44.0–11.44.19, 11.46.0–11.46.19.

**Is there a fix for CVE-2026-77101?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-77101 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-77101?** Check whether you run Commvault CommServe at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a stack-based buffer overflow in CommServe, Commvault's central backup and recovery service. The root cause and attack vector are not detailed in the advisory, but the impact is limited to service availability (crash/denial of service). Commvault has issued patches for all supported versions: 11.46.20+, 11.44.20+, 11.40.72+, and 11.36.123+. Customers must upgrade to the resolved maintenance releases.

## Affected products

- Commvault CommServe 11.36.0–11.36.122, 11.40.0–11.40.71, 11.44.0–11.44.19, 11.46.0–11.46.19

## Timeline

- 2026-09-08: disclosed

## References

- [https://documentation.commvault.com/securityadvisories/CV_2026_08_3.html](https://documentation.commvault.com/securityadvisories/CV_2026_08_3.html)

## Related threats

- [Commvault CommServe cryptographic signature verification in privilege management](https://junglewise.ai/threats/cve-2026-77105-commvault-commserve-cryptographic-signature-verification-in)
- [Commvault CommServe path traversal information disclosure](https://junglewise.ai/threats/cve-2026-77104-commvault-commserve-path-traversal-information-disclosure)
- [Commvault CommServe authentication bypass](https://junglewise.ai/threats/cve-2026-77103-commvault-commserve-authentication-bypass)
- [Commvault CommServe heap buffer overflow](https://junglewise.ai/threats/cve-2026-77102-commvault-commserve-heap-buffer-overflow)
- [Commvault CommServe authorization bypass in command execution](https://junglewise.ai/threats/cve-2026-13738-commvault-commserve-authorization-bypass-in-command-execution)