Deserialization in IBM Qiskit Sdk

CVE-2026-19795

Qiskit could allow a local attacker to cause a denial of service due to a stack overflow during deserialization of QPY payloads. A malicious QPY payload can trigger a segmentation fault, causing the application to crash when deserializing untrusted input.

Vulnerability class: Insecure Deserialization

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.001 (1.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 1.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-19795: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-19795?
CVE-2026-19795 is a medium-severity vulnerability in IBM Qiskit Sdk, classified under Deserialization of Untrusted Data. CVSS score: 6.2/10. Published 2026-09-03.
How severe is CVE-2026-19795?
Medium severity. CVSS v3 base score is 6.2 out of 10.