# CVE-2026-86093: IBM Db2 stack-based buffer overflow in DRDA client

Source: https://junglewise.ai/threats/cve-2026-86093-ibm-db2-stack-based-buffer-overflow-in-drda-client  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-10. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-86093 · Severity: high · CVSS 7.5 · Published 2026-09-10

IBM Db2 is a widely-used enterprise database system. The vulnerability allows an attacker who can intercept or control the database server connection to execute arbitrary code on database clients, potentially leading to data theft or system compromise. This requires network access to the server endpoint but does not require user authentication to the database itself.

Technologies: [IBM Db2](https://junglewise.ai/threats/technologies/db2). Vendors: [IBM](https://junglewise.ai/threats/vendors/ibm).

## Quick answers

**Is CVE-2026-86093 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-86093 being exploited in the wild.

**How severe is CVE-2026-86093?** High severity, with a CVSS score of 7.5, published 10 September 2026.

**Which products and versions are affected?** IBM Db2 11.5.0 through 11.5.9, 12.1.0 through 12.1.5.

**Is there a fix for CVE-2026-86093?** 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-2026-86093 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-86093?** Check whether you run IBM Db2 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

A stack-based buffer overflow (CWE-121) exists in IBM Db2 versions 11.5.0–11.5.9 and 12.1.0–12.1.5 in the DRDA (Distributed Relational Database Architecture) client protocol handler. The vulnerability stems from improper bounds checking when copying user-controlled data from a DRDA server response into a fixed-size stack buffer. An attacker with the ability to control or impersonate a DRDA server endpoint can craft malicious protocol messages to overflow the buffer and execute arbitrary commands on the Db2 client. The attack vector is network-based and requires the ability to intercept or control the server endpoint; no client-side user interaction is required. IBM has released security updates for supported versions (V11.5.9 and V12.1.4/V12.1.5) available through Fix Central.

## Affected products

- IBM Db2 11.5.0 through 11.5.9, 12.1.0 through 12.1.5

## Timeline

- 2026-09-10: disclosed

## References

- [https://www.ibm.com/support/pages/node/7286993](https://www.ibm.com/support/pages/node/7286993)

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