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Public proof of concept

CVE-2026-8836

A public proof of concept exists; no exploitation attested.

  • Published2026-05-18
  • WeaknessCWE-119 · CWE-121

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability was found in lwIP up to 2.2.1. Affected is the function snmp_parse_inbound_frame of the file src/apps/snmp/snmp_msg.c of the component snmpv3 USM Handler. Performing a manipulation of the argument msgAuthenticationParameters results in stack-based buffer overflow. The attack may be initiated remotely. The patch is named 0c957ec03054eb6c8205e9c9d1d05d90ada3898c. It is suggested to install a patch to address this issue. Two separate issue reports were submitted to the project. Their processing was merged as a duplicate.

Timeline

dates in UTC
  1. 2026-05-1819:16CVE publishedNVD
  2. 2026-10-2319:23First public proof of conceptPoC-in-GitHub

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-8836?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-8836?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2026-8836 yet.

Full record on NVD

Fix

No fix published by the sources we read yet. NVD record

Detection

read 2026-10-23 19:25 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
1 repository, unverifiedHunt-Benito/lwip-snmpv3-stack-overflow-cve-2026-8836-critical-embedded-rce
PoC-in-GitHub

Sources

  • NVDCVE recordread 2026-10-23
  • CISA-ADPSSVC decisionnone2026-05-18
  • OpenCVESSVC decisionnone—
  • CNACVSS 4.08.9read 2026-10-23
  • CNACVSS 3.19.8read 2026-10-23
  • CNACVSS 2.010read 2026-10-23
  • CNAweakness (CWE)CWE-119, CWE-121read 2026-10-23
  • FIRST EPSSEPSS score1.6 %2026-10-23
  • PoC-in-GitHubproof of concept1read 2026-10-23

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 4.0 vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published
2026-05-18
Last Modified
2026-08-22
NVD status
Deferred

Frequently asked questions

What is CVE-2026-8836?

A vulnerability was found in lwIP up to 2.2.1. Affected is the function snmp_parse_inbound_frame of the file src/apps/snmp/snmp_msg.c of the component snmpv3 USM Handler. Performing a manipulation of the argument msgAuthenticationParameters results in stack-based buffer overflow. The attack may be initiated remotely. The patch is named 0c957ec03054eb6c8205e9c9d1d05d90ada3898c. It is suggested to install a patch to address this issue. Two separate issue reports were submitted to the project. Their processing was merged as a duplicate.

Is CVE-2026-8836 actively exploited?

Active exploitation of CVE-2026-8836 has not been confirmed. Its EPSS score was 1.6% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-8836?

CVE-2026-8836 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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