CVE-2021-21827

A heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs Xmill 0.7. Within `DecodeTreeBlock` which is called during the decompression of an XMI file, a UINT32 is loaded from the file and used as trusted input as the length of a buffer. An attacker can provide a malicious file to trigger this vulnerability.

• CWE-120
• CWE-787

• https://talosintelligence.com/vulnerability_reports/TALOS-2021-1291Exploit, Third Party Advisory
• https://talosintelligence.com/vulnerability_reports/TALOS-2021-1291Exploit, Third Party Advisory

Published

Aug 20, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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