What is CVE-2026-71558?

CVE-2026-71558 is a critical-severity vulnerability in Apache Fory, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-08-07.

How severe is CVE-2026-71558?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Deserialization in Apache Fory

CVE-2026-71558

Heap type confusion vulnerability in Apache Fory C++ deserialization. This issue affects Apache Fory C++ versions from 0.14.0 before 1.5.0. A crafted input payload can bypass type compatibility checks during polymorphic smart-pointer deserialization, causing an object of an incompatible type to be treated as the declared base type. This may result in undefined behavior and potentially lead to denial of service or arbitrary code execution. Users are recommended to upgrade to Apache Fory 1.5.0, which fixes this issue. Applications not using Apache Fory C++ polymorphic smart-pointer deserialization are not affected.

Vulnerability class: Insecure Deserialization

EPSS: 0.005 (43.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Apache Fory
Apache Software Foundation Fory — versions 0.14.0

Weakness classification (CWE)

References

security@apache.org (vendor-advisory, Mailing List, Vendor Advisory)
af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)

Frequently asked questions

What is CVE-2026-71558?: CVE-2026-71558 is a critical-severity vulnerability in Apache Fory, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-08-07.
How severe is CVE-2026-71558?: Critical severity. CVSS v3 base score is 9.8 out of 10.