Description
An out-of-bounds read vulnerability in the QTextCodec TSCII encoding of the Qt 5 Compatibility APIs module (Qt Core in Qt 5 and earlier) impacts Qt. Applications that convert text to the TSCII encoding through QTextCodec may read memory outside the input buffer, which can cause the application to crash or misinterpret the data.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| qt | Qt | 4.0.0 – ≤ 6.8.8, 6.9.0 – ≤ 6.11.2 | — |
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 | qt6-5compat +1 | No fix yet | — |
| Debian 13 | qt6-5compat +1 | No fix yet | — |
| Debian 12 | qt6-5compat +1 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | qt6-5compat | No fix yet | — |
| Ubuntu 26.04 LTS | qt6-5compat | No fix yet | — |
| Ubuntu 24.04 LTS | qt6-5compat | No fix yet | — |
| Ubuntu 22.04 LTS | qt6-5compat | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | qt6 +3 | 6.12.0-1.hum1 | RHSA-2026:89193 |
Advisories 2
- 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