← Vulnerability feed

Vulnerability record · CVE-2021-21811 · published 31 August 2021

CVE-2021-21811: Att xmill vulnerability

Att · Xmill

A memory corruption vulnerability exists in the XML-parsing CreateLabelOrAttrib functionality of AT&T Labs’ Xmill 0.7. A specially crafted XML file can lead to a heap buffer overflow. An attacker can provide a malicious file to trigger this vulnerability.

9.8 CVSS 3.1 Critical EPSS 1.1% · top 34.8% CWE-191 · CWE-191
9.8CVSS 3.1 base score, v2 7.5
1.1%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

A memory corruption vulnerability exists in the XML-parsing CreateLabelOrAttrib functionality of AT&T Labs’ Xmill 0.7. A specially crafted XML file can lead to a heap buffer overflow. An attacker can provide a malicious file to trigger this vulnerability.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

Track CVE-2021-21811 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2022-26507Att xmill out-of-bounds write vulnerabilityA heap-based buffer overflow exists in XML Decompression DecodeTreeBlock in AT&T Labs Xmill 0.7. A crafted input file can lead to remote code executi…EPSS 2.4%9.8CVE-2021-21826Att xmill classic buffer overflow vulnerabilityA heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs Xmill 0.7. Within `DecodeTreeBl…EPSS 1.1%9.8CVE-2021-21827Att xmill classic buffer overflow vulnerabilityA heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs Xmill 0.7. Within `DecodeTreeBl…EPSS 1.1%9.8CVE-2021-21828Att xmill classic buffer overflow vulnerabilityA heap-based buffer overflow vulnerability exists in the XML Decompression DecodeTreeBlock functionality of AT&T Labs Xmill 0.7. In the default case …EPSS 1.1%9.8CVE-2021-21825Att xmill heap-based buffer overflow vulnerabilityA heap-based buffer overflow vulnerability exists in the XML Decompression PlainTextUncompressor::UncompressItem functionality of AT&T Labs’ Xmill 0.…EPSS 2.3%9.8CVE-2021-21810Att xmill heap-based buffer overflow vulnerabilityA memory corruption vulnerability exists in the XML-parsing ParseAttribs functionality of AT&T Labs’ Xmill 0.7. A specially crafted XML file can lead…EPSS 1.1%9.8CVE-2021-21829Att xmill heap-based buffer overflow vulnerabilityA heap-based buffer overflow vulnerability exists in the XML Decompression EnumerationUncompressor::UncompressItem functionality of AT&T Labs’ Xmill …EPSS 2.5%9.8CVE-2021-21830Att xmill heap-based buffer overflow vulnerabilityA heap-based buffer overflow vulnerability exists in the XML Decompression LabelDict::Load functionality of AT&T Labs’ Xmill 0.7. A specially crafted…EPSS 2.3%

Source: NIST National Vulnerability Database (record CVE-2021-21811), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.