Security readout for executives and security teams
Plain-English summary
This is a critical Cisco issue affecting Expressway Series and TelePresence VCS management/API surfaces. A remote attacker with high privileges could overwrite files or abuse null byte handling, creating serious risk to confidentiality and integrity on collaboration infrastructure.
Executive priority
Treat as high-priority for Cisco collaboration infrastructure, especially internet-adjacent or broadly reachable management surfaces. The privilege requirement lowers mass-exploitation likelihood, but successful abuse could affect sensitive systems and operational trust.
Technical view
CVE-2022-20813 covers API and web-based management interface flaws in Cisco Expressway Series and Cisco TelePresence VCS. CVSS 3.1 is 9.0: network exploitable, low complexity, high privileges required, no user interaction, changed scope, high confidentiality and integrity impact, low availability impact.
Likely exposure
Exposure is most likely where Cisco Expressway-C, Expressway-E, or Cisco TelePresence VCS management/API interfaces are reachable by administrators or management networks. The source bundle does not provide affected version ranges.
Exploitation context
The source bundle does not show CISA KEV listing and provides no evidence of active exploitation. Exploitation is described as remote and low-complexity, but requiring high privileges, which reduces broad opportunistic risk while keeping insider or compromised-admin risk serious.
Researcher notes
Key uncertainty is affected version detail: the bundle lists the product family but not release ranges or fixed versions. Validate against Cisco’s advisory before scoping remediation. Do not assume active exploitation from the provided evidence.
Mitigation direction
- Review Cisco’s advisory for affected releases and fixed software.
- Apply Cisco-recommended updates or mitigations where applicable.
- Restrict management and API access to trusted administrative networks.
- Review privileged administrator accounts for necessity and compromise indicators.
- Prioritize devices exposed to broader internal or external networks.
Validation and detection
- Inventory Cisco Expressway-C, Expressway-E, and TelePresence VCS deployments.
- Compare installed versions against Cisco’s advisory guidance.
- Confirm management and API interfaces are not broadly reachable.
- Review logs for unusual privileged management activity.
- Verify remediation status after applying Cisco guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-158: Exact CWE lookup
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Open ATT&CK lookupCVE-2022-20813 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:L
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.
CVSS vector scores
1 official scoreWe 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.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:L2.36Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9CriticalVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:L
Source materials
- CVE List V5 sourceCVE List V5
- 20220706 Cisco Expressway Series and Cisco TelePresence Video Communication Server VulnerabilitiesCVE reference · vendor-advisory, x_refsource_CISCO
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Null Byte or NUL Character
Improper Neutralization of Null Byte or NUL Character represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.