CVE-2026-91018 (GCVE-0-2026-91018)

Vulnerability from cvelistv5 – Published: 2026-09-22 20:25 – Updated: 2026-09-22 20:25
VLAI
Title
Double Free in lwIP (lightweight IP)
Summary
lwIP (Lightweight IP) has a double free vulnerability, which could crash the system, cause a DoS, memory corruption, or allow code execution on the victim system.
Severity
8.8 (High)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.7 (High)
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
lwIP lwIP API Affected: 2.0.1 , ≤ 2.2.1 (custom)
guessed Create a notification for this product.
Date Public
2026-09-22 17:53
Credits
Eric Evenchick of Tetrel Security reported this vulnerability to CISA.
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

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  • 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.



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