CVE-2026-111137

libsmi through 0.5.0 contains an out-of-bounds write vulnerability in smiValueAsString() in lib/smi.c that allows attackers to overflow a fixed 1024-byte static buffer through hex rendering of OCTET STRING values. Attackers can supply a crafted MIB with an OCTET STRING DEFVAL of 512 or more octets and a leading 0x00 byte to corrupt adjacent library globals and crash smidump or other consumers.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/amartin755/libsmi
https://github.com/amartin755/libsmi/blob/c58307210fe995ec419db976eb234aebc71a9216/lib/smi.c#L479-L566
https://hackmd.io/@haind-pwn/libsmi-smivalueasstring-octetstring-defval-oob-write
https://www.vulncheck.com/advisories/libsmi-through-0.5.0-out-of-bounds-write-via-smivalueasstring-octet-string-defval

Configurations

No configuration.

History

15 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 19:17

Updated : 2026-10-16 18:25

NVD link : CVE-2026-111137

Mitre link : CVE-2026-111137

CVE.ORG link : CVE-2026-111137

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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