Vulnerability Report

CVE-2026-8836

Title: Stack-based buffer overflow in lwIP SNMPv3 USM Handler

Buffer Overflow

Proof Of Concept

PoC Available for CVE-2026-8836

CWE Category CWE-119

Published Date May 18, 2026

Modified Date May 18, 2026

Exploit Status Available

Score 9.3 CVSS v4.0

Exploit Probability (EPSS)

0.86%

Vulnerability Summary

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.

Impacted Vendors

Analysis in Progress...

Reference Links

https://cgit.git.savannah.gnu.org/cgit/lwip.git/commit/?id=0c957ec03054eb6c8205e9c9d1d05d90ada3898c https://github.com/lwip-tcpip/lwip/commit/0c957ec03054eb6c8205e9c9d1d05d90ada3898c https://savannah.nongnu.org/bugs/?68194 https://vuldb.com/submit/829798 https://vuldb.com/vuln/364474 https://vuldb.com/vuln/364474/cti

CVSS v4.0

Source Entity [email protected]

Severity CRITICAL

9.3

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

N/A

RAW 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:X/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

CVSS v3.1

Source Entity [email protected]

Severity CRITICAL

9.8

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0

Source Entity [email protected]

Severity HIGH

10.0

Access Vector

N/A

Authentication

N/A

RAW VECTOR AV:N/AC:L/Au:N/C:C/I:C/A:C

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-8836 Exploits & PoCs (Proof Of Concept)

GitHub https://github.com/Hunt-Benito/lwip-snmpv3-stack-overflow-cve-2026-8836-critical-embedded-rce

View Code

May 18, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


                                    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:X/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

Affected Stack

No specific products linked.