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CVE-2021-21826

Published: Aug 20, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDU csafCWE-120
9.8CRITICAL
NVD MITRE
EPSS Score
1.1%
Top 36.5%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available
Self-Check
OpenVAS

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-120CWE-787

Affected Products

Schneider Electric
commercial·FRaka schneider-electric
EcoStruxure Control Expert
ICS / OT / IoT
SCADAPack RemoteConnect
ICS / OT / IoT
EcoStruxure Process Expert
ICS / OT / IoT
att
commercial·USaka u-verse firmware, xmill, winvnc
xmillMixed
Communications / video-conferencing
AT&T Labs
oss-project·US
XmillOn-prem
DevTools & CI / build-test-tools
and 1 more affected products View all →

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1291
talosintelligence.com
https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2022/icsa-22-223-03.json
raw.githubusercontent.com
https://www.cisa.gov/news-events/ics-advisories/icsa-22-223-03
cisa.gov
and 22 more references View all →

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