Description
Out-of-bounds read in the QAuthenticator NTLM authentication handling in the Qt Network module in Qt Group Qt allows remote attackers to obtain sensitive information (heap memory contents) or cause a denial of service (application crash) via a crafted NTLM challenge sent by a malicious server or proxy, when an application using QNetworkAccessManager or QTcpSocket authenticates with NTLM.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| qt | qt | 6.8.0 – < 6.8.10, 6.9.0 – < 6.11.2 | 6.8.10 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | qt6-base | 6.11.2+dfsg-5 | — |
| Debian 14 | qtbase-opensource-src | No fix yet | — |
| Debian 13 | qt6-base +1 | No fix yet | — |
| Debian 12 | qt6-base +1 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | qt6-base +1 | No fix yet | — |
| Ubuntu 26.04 LTS | qt6-base +1 | No fix yet | — |
| Ubuntu 24.04 LTS | qt6-base | No fix yet | — |
| Ubuntu 22.04 LTS | qt6-base | No fix yet | — |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | qtbase-opensource-src | No fix yet | — |
| Ubuntu Pro 22.04 LTS | qtbase-opensource-src | No fix yet | — |
| Ubuntu Pro 20.04 LTS | qtbase-opensource-src | No fix yet | — |
| Ubuntu Pro 18.04 LTS | qtbase-opensource-src | No fix yet | — |
| Ubuntu Pro 16.04 LTS | qtbase-opensource-src | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | qt5 +3 | 5.15.18-3.1.hum1 | RHSA-2026:80566 |
| Red Hat Hardened Images 1 | qt6 +3 | 6.12.0-1.hum1 | RHSA-2026:89193 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | qtbase | No fix yet | — |
Advisories 3
- RHSA-2026:80566 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- RHSA-2026:89193 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- WID-SEC-2026-4178 QT: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 27, 2026