TI-2021-04856 Aliases CVE-2021-21811 GHSA-fmqr-7vvj-9r72

Integer underflow in AT&T

MEDIUM 44CWE-191Published 2021-08-31 · Updated 2024-08-03

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-191 and the CVSS impact.

Summary

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.

Why it matters now

EPSS 0.01136 66th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	AT&T	AT&T Labs Xmill 0.7	—	No fix listed	CNA

AT&T Vendor— Affected AT&T Labs Xmill 0.7 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:att:xmill:0.7:::::::*	0.7	Vulnerable	AT&T

cpe:2.3:a:att:xmill:0.7:*:*:*:*:*:*:* Versions 0.7 Vulnerable ·AT&T

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-21811
2026-10-03 Alias added: GHSA-fmqr-7vvj-9r72

References

Exploit 1

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1279

TI-2022-09848 A heap-based buffer overflow exists in XML Decompression DecodeTreeBlock in AT&T Labs… CVSS 3.1CRITICAL 9.8
TI-2021-04874 Heap-based buffer overflow in AT&T CVSS 3.1CRITICAL 9.8
TI-2021-04875 Heap-based buffer overflow in AT&T CVSS 3.1CRITICAL 9.8
TI-2021-04870 Heap-based buffer overflow in AT&T CVSS 3.1CRITICAL 9.8
TI-2021-04873 Buffer overflow in AT&T CVSS 3.1CRITICAL 9.8
TI-2021-04872 Buffer overflow in AT&T CVSS 3.1CRITICAL 9.8

See all 12 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences