CVE-2026-55971: Apache Thrift: C++ ZLIB heap buffer overflow (write) in THeaderTransport::untransform()

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-27 · updated 2026-10-24
Weakness: CWE-122

Description

Heap-based Buffer Overflow vulnerability in Apache Thrift C++ bindings. This issue affects Apache Thrift: before 0.24.0. Users are recommended to upgrade to version 0.24.0, which fixes the issue.

Affected products

Apache Software Foundation Apache Thrift: before 0.24.0 — fixed in 0.24.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Thrift 0.24.0. Check the vendor advisory for mitigations.

References

https://lists.apache.org/thread/7v3jhgwfbmhx42424phydlnzb109g8b9
https://lists.apache.org/thread/xjs36m6kjxpmrmzwck636msg3nvoqnmx
http://www.openwall.com/lists/oss-security/2026/07/24/42

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