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CVE Record

CVE-2021-1450: Cisco AnyConnect Secure Mobility Client Denial of Service Vulnerability

A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected device. To exploit this vulnerability, the attacker would need to have valid credentials on the device. The vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending one or more crafted IPC messages to the AnyConnect process on an affected device. A successful exploit could allow the attacker to stop the AnyConnect process, causing a DoS condition on the device. Note: The process under attack will automatically restart so no action is needed by the user or admin.

MediumCVSS 5.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

A logged-in local user could crash Cisco AnyConnect on an affected device by sending malformed IPC messages. The process restarts automatically, but VPN availability may still be interrupted. This is not described as remote code execution or data theft, and the provided sources do not show active exploitation.

Executive priority

Treat as a moderate endpoint availability issue. It is most urgent where VPN stability is operationally important or where many users have local access to shared systems.

Technical view

CVE-2021-1450 is a CWE-20 input-validation flaw in Cisco AnyConnect Secure Mobility Client IPC handling. CVSS 3.1 is 5.5 with local attack vector, low complexity, low privileges, no user interaction, and availability-only impact. The affected process automatically restarts after the denial-of-service condition.

Likely exposure

Exposure is limited to systems running affected Cisco AnyConnect Secure Mobility Client where an attacker already has valid local credentials. The source bundle does not provide affected version ranges.

Exploitation context

The attacker must be authenticated locally on the target device. The provided sources describe crafted IPC messages causing the AnyConnect process to stop, but do not cite public exploitation or CISA KEV listing.

Researcher notes

The source bundle identifies insufficient input validation in the IPC channel. Scope is unchanged, privileges required are low, and impact is availability only. Version and fix details are incomplete in the provided data, so rely on Cisco advisory confirmation.

Mitigation direction

  • Review Cisco advisory for affected and fixed AnyConnect releases.
  • Update Cisco AnyConnect according to vendor guidance.
  • Restrict local account access to trusted users only.
  • Monitor AnyConnect process crashes or repeated restarts.
  • Prioritize managed endpoints with shared or weak local access controls.

Validation and detection

  • Inventory endpoints running Cisco AnyConnect Secure Mobility Client.
  • Compare installed versions against Cisco advisory guidance.
  • Confirm whether local non-admin users can access affected endpoints.
  • Review endpoint logs for AnyConnect crash or restart patterns.
  • Document compensating controls for systems awaiting vendor remediation.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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cwe · low confidence lookup

CWE-20: Exact CWE lookup

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cve · low confidence lookup

CVE-2021-1450 mapping review

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
5.5 (3.1)
Known Exploited
No
Published

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

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
5.5CVSS 3.1MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H1.83.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

5.5Medium
CVSS 3.1 vector shape for CVE-2021-1450Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
CiscoCisco AnyConnect Secure Mobility Clientn/aListed
Weakness

CWE details

CWE-20

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.