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CVE Record

CVE-2021-1311: Cisco Webex Meetings and Cisco Webex Meetings Server Host Key Brute Forcing Vulnerability

A vulnerability in the reclaim host role feature of Cisco Webex Meetings and Cisco Webex Meetings Server could allow an authenticated, remote attacker to take over the host role during a meeting. This vulnerability is due to a lack of protection against brute forcing of the host key. An attacker could exploit this vulnerability by sending crafted requests to a vulnerable Cisco Webex Meetings or Webex Meetings Server site. A successful exploit would require the attacker to have access to join a Webex meeting, including applicable meeting join links and passwords. A successful exploit could allow the attacker to acquire or take over the host role for a meeting.

MediumCVSS 5.4Not KEV-listedUpdated
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This flaw lets someone who can already enter a Cisco Webex meeting try to take the host role by brute forcing the host key. It does not describe full platform compromise, but host takeover can disrupt meetings, change controls, and undermine trust in sensitive sessions.

Executive priority

Treat this as a moderate business risk for organizations using Webex for executive, customer, legal, or operationally sensitive meetings. Prioritize verification and Cisco-guided remediation, but this is not evidenced as internet-wide unauthenticated compromise.

Technical view

CVE-2021-1311 affects the reclaim host role feature in Cisco Webex Meetings and Cisco Webex Meetings Server. The issue is missing brute-force protection for the host key, classified as CWE-307. CVSS 3.1 is 5.4 with network access and low privileges required.

Likely exposure

Exposure is most relevant to organizations using Cisco Webex Meetings or Webex Meetings Server for protected meetings. The provided bundle does not identify affected versions beyond the product names, so teams must verify exact exposure against Cisco guidance.

Exploitation context

The attacker must be authenticated enough to join the target Webex meeting and have any required join links or passwords. The bundle does not cite active exploitation, public weaponization, or CISA KEV listing.

Researcher notes

Key constraint is prerequisite meeting access, reflected by PR:L. Impact is limited confidentiality but low integrity and availability impact through host role takeover. The bundle lacks version and fix detail, so avoid assumptions beyond Cisco’s advisory.

Mitigation direction

  • Review the Cisco advisory for affected and fixed release details.
  • Apply Cisco-recommended updates or service-side remediations where applicable.
  • Restrict meeting links and passwords to intended participants only.
  • Use stronger meeting access controls for sensitive meetings.
  • Reissue or rotate meeting details after suspected unauthorized access.

Validation and detection

  • Inventory Cisco Webex Meetings Server deployments and managed Webex sites.
  • Compare deployment details against Cisco advisory affected-version guidance.
  • Confirm sensitive meetings require appropriate passwords or access controls.
  • Review meeting records for unexpected host role changes where available.
Prepared
Confidence
medium
Sources
3

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

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-307: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-1311 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Medium
CVSS
5.4 (3.1)
Known Exploited
No
Published

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

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
5.4CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L2.82.5Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

5.4Medium
CVSS 3.1 vector shape for CVE-2021-1311Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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 WebEx Meetings Servern/aListed
Weakness

CWE details

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

CWE-307 · source CWE mapping

Improper Restriction of Excessive Authentication Attempts

Improper Restriction of Excessive Authentication Attempts represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.