Description
An issue was discovered in Qt before 5.15.14, 6.x before 6.2.9, and 6.3.x through 6.5.x before 6.5.1. Qt Network incorrectly parses the strict-transport-security (HSTS) header, allowing unencrypted connections to be established, even when explicitly prohibited by the server. This happens if the case used for this header does not exactly match.
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 | 6.4.2+dfsg-9 | — |
| Debian 14 | qtbase-opensource-src | 5.15.8+dfsg-10 | — |
| Debian 13 | qt6-base | 6.4.2+dfsg-9 | — |
| Debian 13 | qtbase-opensource-src | 5.15.8+dfsg-10 | — |
| Debian 12 | qt6-base | 6.4.2+dfsg-9 | — |
| Debian 12 | qtbase-opensource-src | 5.15.8+dfsg-10 | — |
| Debian 10 | qtbase-opensource-src | 5.11.3+dfsg1-1+deb10u6 | DLA-3805-1 |
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 25.10 | qt6-base +1 | No fix yet | — |
| Ubuntu 24.04 LTS | qt6-base +1 | No fix yet | — |
| Ubuntu 22.04 LTS | qt6-base +1 | No fix yet | — |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | qtbase-opensource-src-gles | No fix yet | — |
| Ubuntu 16.04 LTS | qtbase-opensource-src-gles | No fix yet | — |
| Ubuntu Pro 22.04 LTS | qtbase-opensource-src | 5.15.3+dfsg-2ubuntu0.2+esm1 | USN-7780-1 |
| Ubuntu Pro 20.04 LTS | qtbase-opensource-src | 5.12.8+dfsg-0ubuntu2.1+esm1 | USN-7780-1 |
| Ubuntu Pro 18.04 LTS | qtbase-opensource-src | 5.9.5+dfsg-0ubuntu2.6+esm1 | USN-7780-1 |
| Ubuntu Pro 16.04 LTS | qtbase-opensource-src | 5.5.1+dfsg-16ubuntu7.7+esm1 | USN-7780-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | libqt5-qtbase | 5.15.8+kde185-150500.4.8.1 | SUSE-SU-2023:3018-1 |
| SLES 15 SP5 | qt6-base | 6.4.2-150500.3.7.4 | SUSE-SU-2023:3225-1 |
| SLES 15 SP4 | libqt5-qtbase | 5.15.2+kde294-150400.6.6.1 | SUSE-SU-2023:2982-1 |
| SLES 15 SP4 | qt6-base | 6.2.2-150400.4.6.1 | SUSE-SU-2023:3380-1 |
| SLES 15 SP3 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SLES 15 SP2 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP3 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SLES for SAP 15 SP2 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SLE HPC 15 SP3 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SLE HPC 15 SP2 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SUSE Manager Server 4.2 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SUSE Manager Proxy 4.2 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SUSE Enterprise Storage 7.1 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
| SUSE Enterprise Storage 7 | libqt5-qtbase | 5.12.7-150200.4.23.1 | SUSE-SU-2023:3207-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libqt5-qtbase | 5.15.9+kde154-1.1 | openSUSE-SU-2024:12955-1 |
| openSUSE Tumbleweed | qt6-base | 6.5.3-2.1 | openSUSE-SU-2024:13289-1 |
| openSUSE Leap 15.5 | libqt5-qtbase | 5.15.8+kde185-150500.4.8.1 | SUSE-SU-2023:3018-1 |
| openSUSE Leap 15.5 | qt6-base | 6.4.2-150500.3.7.4 | SUSE-SU-2023:3225-1 |
| openSUSE Leap 15.5 | qt6-base-docs | 6.4.2-150500.3.7.1 | SUSE-SU-2023:3225-1 |
| openSUSE Leap 15.4 | libqt5-qtbase | 5.15.2+kde294-150400.6.6.1 | SUSE-SU-2023:2982-1 |
| openSUSE Leap 15.4 | qt6-base +1 | 6.2.2-150400.4.6.1 | SUSE-SU-2023:3380-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.24 | qt6-qtbase | 6.5.0-r5 | — |
| Alpine v3.23 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.23 | qt6-qtbase | 6.5.0-r5 | — |
| Alpine v3.22 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.22 | qt6-qtbase | 6.5.0-r5 | — |
| Alpine v3.21 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.21 | qt6-qtbase | 6.5.0-r5 | — |
| Alpine v3.20 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.20 | qt6-qtbase | 6.5.0-r5 | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.19 | qt6-qtbase | 6.5.0-r5 | — |
| Alpine v3.18 | qt5-qtbase | 5.15.9_git20230505-r0 | — |
| Alpine v3.18 | qt6-qtbase | 6.5.0-r5 | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | qt5-qtbase +10 | 5.9.2-3.amzn2.0.10 | ALAS2-2023-2227 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | qt5-qtbase | 5.12.11-8 | — |
Advisories 12
- WID-SEC-2023-2917 Xerox FreeFlow Print Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jun 30, 2026
- USN-7780-1 qtbase-opensource-src vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026
- DLA-3805-1 qtbase-opensource-src - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:12955-1 libQt5Bootstrap-devel-static-32bit-5.15.9+kde154-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:3207-1 Security update for libqt5-qtbase SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:3380-1 Security update for qt6-base SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:2982-1 Security update for libqt5-qtbase SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2023:3018-1 Security update for libqt5-qtbase SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2023-1294 QT: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 28, 2025
- openSUSE-SU-2024:13289-1 libQt6Concurrent6-6.5.3-2.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- SUSE-SU-2023:3225-1 Security update for qt6-base SUSE / openSUSE Security Updates · May 2, 2025
- ALAS2-2023-2227 Moderate: qt5-qtbase security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Sep 7, 2023
References
- https://codereview.qt-project.org/c/qt/qtbase/+/476140
- https://github.com/qt/qtbase/commit/1b736a815be0222f4b24289cf17575fc15707305
- https://lists.qt-project.org/pipermail/announce/2023-May/000414.html
- [debian-lts-announce] 20240430 [SECURITY] [DLA 3805-1] qtbase-opensource-src security update mailing-list