Security readout for executives and security teams
Plain-English summary
CVE-2021-1438 lets a low-privileged local user on Cisco WAAS read files they should not access. The impact is confidentiality-focused: sensitive configuration or operational data could be exposed. The source bundle does not show remote code execution or active exploitation.
Executive priority
Prioritize this where WAAS devices hold sensitive configuration data or have broad local user access. It is not a headline remote compromise, but it can expose confidential files after account compromise or insider misuse.
Technical view
Cisco WAAS CLI command handling lacks proper input validation and authorization for specific commands. An authenticated local attacker with low privileges can trigger arbitrary file reads outside their permissions. CVSS 3.1 is 5.5, with local access, low complexity, and high confidentiality impact.
Likely exposure
Exposure is limited to organizations running Cisco Wide Area Application Services Software where attackers can obtain local authenticated CLI access. The bundle does not provide affected version ranges, so teams must verify installed versions against Cisco guidance.
Exploitation context
The attacker must already authenticate locally to the affected WAAS device. CISA KEV status is false in the bundle, and no cited source states active exploitation. Treat this as an insider, compromised-account, or post-access confidentiality risk.
Researcher notes
The evidence supports CWE-668, local attack vector, low privileges, no user interaction, unchanged scope, high confidentiality impact, and no integrity or availability impact. Version details are not present in the bundle, so affected-release confirmation depends on Cisco’s advisory.
Mitigation direction
- Check the Cisco advisory for affected releases and fixed software guidance.
- Inventory Cisco WAAS devices and record installed software versions.
- Restrict local CLI access to trusted administrative users only.
- Review low-privilege accounts on WAAS devices for unnecessary access.
- Monitor vendor guidance because the bundle does not name fixed versions.
Validation and detection
- Confirm whether Cisco WAAS Software is deployed in the environment.
- Compare each WAAS software version against the Cisco advisory.
- Review local WAAS user accounts and assigned privileges.
- Check administrative logs for unusual authenticated CLI activity.
- Document whether exposed devices contain sensitive local files.
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
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-668: 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 lookupCVE-2021-1438 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
- 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:H/I:N/A:N
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:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20210505 Cisco Wide Area Application Services Software Information Disclosure VulnerabilityCVE 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.
Exposure of Resource to Wrong Sphere
Exposure of Resource to Wrong Sphere represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.