Description
An out-of-bounds write vulnerability in the Qt QTextCodec iconv-based encoding of the Qt 5 Compatibility APIs module (Qt Core in Qt 5 and earlier) impacts Qt. Under certain conditions, encoding text with QTextCodec may write outside an internal buffer. This can cause the application to crash and may affect data integrity.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| qt | Qt | 4.5.0 – ≤ 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