Security readout for executives and security teams
Plain-English summary
CVE-2021-47827 is a denial-of-service issue in WebSSH for iOS 14.16.10. The reported impact is that malformed pasted input in the mashREPL tool can crash the mobile application. This threatens availability of the app for affected users, not data confidentiality or integrity based on the provided sources.
Executive priority
Treat as a targeted availability issue for mobile SSH workflows. It is not currently supported as active exploitation or data theft. Prioritize remediation if WebSSH is used for operations, administration, or incident response where app crashes could delay work.
Technical view
The vulnerability is reported as CWE-1284 improper validation of specified quantity in input. Sources describe a crash condition in mashREPL when malformed input is pasted. The CVSS 3.1 score is 7.5, with availability impact only. A public ExploitDB reference exists, but the bundle does not show CISA KEV listing or confirmed active exploitation.
Likely exposure
Exposure appears limited to organizations or users running WebSSH for iOS version 14.16.10 and using mashREPL. The provided sources do not establish broader version impact, server-side exposure, or impact to SSH services themselves.
Exploitation context
A public exploit reference is cited, but active exploitation is not supported by KEV or the provided sources. The described outcome is application crash through malformed input handling, so practical risk is disruption of WebSSH use rather than system compromise.
Researcher notes
Evidence is limited to the CVE record, VulnCheck advisory, App Store product page, and ExploitDB reference. The CVSS vector says network/no user interaction, while the description emphasizes pasted input. Do not assume additional affected versions or a vendor fix without confirmation.
Mitigation direction
- Inventory iOS devices for WebSSH version 14.16.10.
- Check the App Store and vendor guidance for an updated WebSSH release.
- Prioritize updating or replacing affected installations where WebSSH is operationally important.
- Limit use of mashREPL with untrusted pasted content until vendor guidance is confirmed.
- Use MDM policy where appropriate to manage app version compliance.
Validation and detection
- Confirm whether WebSSH for iOS 14.16.10 is installed in managed device inventories.
- Review vendor, App Store, and advisory sources for fixed-version information.
- Validate suspected exposure only in an isolated test device, without production accounts.
- Document whether mashREPL is used by affected teams.
- Monitor helpdesk reports for repeat WebSSH crashes on iOS devices.
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-1284: 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-2021-47827 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
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- ExploitDB-49883CVE reference · exploit
- WebSSH iOS App Store PageCVE reference · product
- VulnCheck Advisory: WebSSH for iOS 14.16.10 - 'mashREPL' Denial of ServiceCVE reference · third-party-advisory
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 Validation of Specified Quantity in Input
Improper Validation of Specified Quantity in Input represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.