CVE-2026-95509 Out-of-bounds read vulnerability in string formatting impacts Qt for MCUs
An out-of-bounds read in Qt for MCUs string formatting allows attackers to cause crashes or leak memory contents.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-95509?
CVE-2026-95509 is a high-severity memory corruption vulnerability in Qt for MCUs, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Strings optimized for Latin-1 displaying Latin-1 characters cause incorrect String.arg() formatting by an incorrect buffer size calculation, causing out-of-bounds reading.
Which versions are affected by CVE-2026-95509?
How do I fix CVE-2026-95509?
No fix has been published for CVE-2026-95509 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-95509 being exploited?
There is no known exploitation of CVE-2026-95509 in the wild and no public exploit code.
Sources
Also known as GHSA-5q52-pjpv-x8mh.