# CVE-2026-95620: Qt use-after-free in QNetworkAccessManager HTTP/2 support

Source: https://junglewise.ai/threats/cve-2026-95620-a-use-after-free-vulnerability-in-the-qt-qnetworkaccessmanager  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-23. Updated: 2026-10-23  
License: CC BY 4.0 with a link back

CVE-2026-95620 · Severity: info · Published 2026-10-23

Qt is a widely-used cross-platform application framework. A malicious or compromised HTTP/2 server can trigger a use-after-free memory error in applications using Qt's network client, causing them to crash and become unavailable.

Technologies: [Qt](https://junglewise.ai/threats/technologies/qt-qt). Vendors: [Qt](https://junglewise.ai/threats/vendors/qt).

## Quick answers

**Is CVE-2026-95620 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-95620 being exploited in the wild.

**How severe is CVE-2026-95620?** Informational severity, published 23 October 2026.

**Which products and versions are affected?** Qt 6.9.0 to 6.11.2.

**Is there a fix for CVE-2026-95620?** Yes: fixed in Qt 6.11.3, Qt 6.12.0. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-95620 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-95620?** Check whether you run Qt 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.

## How to fix

- Fixed in Qt 6.11.3, Qt 6.12.0

## Technical details

A use-after-free vulnerability exists in Qt's QNetworkAccessManager HTTP/2 client support within the Qt Network module. A malicious or compromised HTTP/2 server can trigger this defect by sending crafted responses, causing the client application to access freed memory and crash. The vulnerability requires only that the application connect to an HTTP/2 server; no authentication or user interaction beyond normal network communication is needed.

## Affected products

- Qt Qt 6.9.0 to 6.11.2

## Timeline

- 2026-10-23: disclosed

## References

- [https://codereview.qt-project.org/c/qt/qtbase/+/759717](https://codereview.qt-project.org/c/qt/qtbase/+/759717)
- [https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products](https://wiki.qt.io/List_of_known_vulnerabilities_in_Qt_products)

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