CVE-2021-47827 (GCVE-0-2021-47827)

Vulnerability from cvelistv5 – Published: 2026-01-16 19:09 – Updated: 2026-01-16 21:32
VLAI
Title
WebSSH for iOS 14.16.10 - 'mashREPL' Denial of Service
Summary
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.
Severity
4.6 (Medium)
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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Assigner
References
Impacted products
Vendor Product Version
WebSSH WebSSH for iOS Affected: 14.16.10
Create a notification for this product.
Date Public
2021-05-18 00:00
Credits
Luis Martinez
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.