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CVE-2026-91135

Apache Thrift: C++ `THeaderTransport::transform()` heap buffer overflow (write direction)

Apache Software Foundation Apache Thrift
CVSS
9.2Critical
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.46%Chance of exploitation activity in the next 30 days, higher than 38% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in0.25.0Fixed versionCVE List
Published2 Oct 2026Updated 2 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Heap-based buffer overflow vulnerability in Apache Thrift C++ THeaderTransport.

When an application enables the ZLIB transform for the frames it sends, THeaderTransport::transform() copies the compressed frame into the write buffer without making sure it fits. Data that does not compress, such as content a remote peer supplied, grows under compression, so the copy writes past the end of the heap buffer by an amount that grows with the size of the frame, and for large frames it also reads past the end of the transform buffer.

This issue affects Apache Thrift: before 0.25.0.

Users are recommended to upgrade to version 0.25.0, which fixes the issue.

Text from CVE List

Affected versions 1

  • Apache Thriftaffected: all versions before 0.25.0CVE List

References 2