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Ios Xe CVE-2021-1619

CRITICAL
Access of Uninitialized Pointer (CWE-824)
2021-09-23 psirt@cisco.com
Buffer Overflow Denial Of Service Memory Corruption Apple Cisco Ios Xe Ios Xe Sd Wan Ios Xe Sd Wan 16 10 1 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 1 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 1 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 1 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 2 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 2 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 2 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 2 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 3 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 3 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 3 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 3 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 3A When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 3A When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 3A When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 3A When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 10 3A When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 3B When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 3B When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 3B When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 3B When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 10 3B When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 4 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 4 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 4 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 4 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 10 4 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 5 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 5 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 5 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 5 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 10 5 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 10 6 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 10 6 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 10 6 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 10 6 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 10 6 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 11 1 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 11 1 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 11 1 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 11 1 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 11 1A When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 11 1A When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 11 1A When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 11 1A When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 11 1A When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 11 1B When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 11 1B When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 11 1B When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 11 1B When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 11 1B When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 11 1D When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 11 1D When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 11 1F When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 11 1S When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 11 1S When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 11 1S When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 11 1S When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 11 1S When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1 When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1A When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1A When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1A When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1A When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1A When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1A When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1B When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1B When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1B When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1B When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1B When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1B When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1B1 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1B1 When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1B1 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1B1 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1B1 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1B1 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1C When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1C When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1C When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1C When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1C When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1C When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1D When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1D When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1D When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1D When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1D When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1D When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 1E When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 1E When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 1E When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 1E When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 1E When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 1E When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 2R When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 2R When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 2R When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 2R When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 2R When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 2R When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 3 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 3 When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 3 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 3 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 3 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 3 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 4 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 4 When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 4 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 4 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 4 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 4 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 4A When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 4A When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 4A When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 12 5 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 12 5 When Installed On 1100 Series Industrial Integrated Services Ios Xe Sd Wan 16 12 5 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 12 5 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 12 5 When Installed On Cloud Services Router 1000V Ios Xe Sd Wan 16 12 5 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 9 1 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 9 1 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 9 1 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 9 1 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 9 2 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 9 2 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 9 2 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 9 2 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 9 3 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 9 3 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 9 3 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 9 3 When Installed On Integrated Services Virtual Ios Xe Sd Wan 16 9 4 When Installed On 1000 Series Integrated Services Ios Xe Sd Wan 16 9 4 When Installed On 4000 Series Integrated Services Ios Xe Sd Wan 16 9 4 When Installed On Asr 1000 Series Aggregation Services Ios Xe Sd Wan 16 9 4 When Installed On Integrated Services Virtual
9.1
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Uninitialized pointer prevention
MITRE ATT&CK

1 technique across 1 tactic: Execution

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Impact

CVSS score of 9.1 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system.

Act Now Prioritize within 24-48h. Why: CRITICAL severity.
No patch listed yet 1.7% exploitation probability (EPSS)

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AnalysisAI

A vulnerability in the authentication, authorization, and accounting (AAA) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass NETCONF or RESTCONF. Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-824. A vulnerability in the authentication, authorization, and accounting (AAA) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass NETCONF or RESTCONF authentication and do either of the following: Install, manipulate, or delete the configuration of an affected device Cause memory corruption that results in a denial of service (DoS) on an affected device This vulnerability is due to an uninitialized variable. An attacker could exploit this vulnerability by sending a series of NETCONF or RESTCONF requests to an affected device. A successful exploit could allow the attacker to use NETCONF or RESTCONF to install, manipulate, or delete the configuration of a network device or to corrupt memory on the device, resulting a DoS. Affected products include: Cisco Ios Xe, Cisco Ios Xe Sd-Wan, Cisco Ios Xe Sd-Wan 16.10.1 When Installed On 1000 Series Integrated Services, Cisco Ios Xe Sd-Wan 16.10.1 When Installed On 4000 Series Integrated Services, Cisco Ios Xe Sd-Wan 16.10.1 When Installed On Asr 1000 Series Aggregation Services.

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  • Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 9.1 CRITICAL
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High

DescriptionNVD

A vulnerability in the authentication, authorization, and accounting (AAA) function of Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass NETCONF or RESTCONF authentication and do either of the following: Install, manipulate, or delete the configuration of an affected device Cause memory corruption that results in a denial of service (DoS) on an affected device This vulnerability is due to an uninitialized variable. An attacker could exploit this vulnerability by sending a series of NETCONF or RESTCONF requests to an affected device. A successful exploit could allow the attacker to use NETCONF or RESTCONF to install, manipulate, or delete the configuration of a network device or to corrupt memory on the device, resulting a DoS.

Threat Intelligence Overview

EPSS Score
1.7%
Top 25% exploitable
Data Quality
2 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity CRITICAL
CISA KEV No
Public POC No
EPSS 1.7%
Patch available No
Active threat No
Deciding rule
CRITICAL severity
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

48
Low Medium High Critical
KEV: 0
EPSS: +2
CVSS: +46
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.

Memory corruption occurs when a program writes data beyond the boundaries of allocated memory regions or accesses memory in unintended ways, violating the integrity of the process's address space.

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.

Affected Products (CPE)NVD

cpe:2.3:o:cisco:ios_xe:16.3.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.1a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.4:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.5:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.5b:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.6:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.7:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.8:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.9:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.10:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.3.11:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.4.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.4.2:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.4.3:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.5.1:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.5.1a:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.5.1b:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe:16.5.2:*:*:*:*:*:*:*
+ 244 more

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