CVE-2026-111137
libsmi through 0.5.0 Out-of-Bounds Write via smiValueAsString OCTET STRING DEFVAL
Description
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.
INFO
Published Date :
Oct. 15, 2026, 7:17 p.m.
Last Modified :
Oct. 16, 2026, 6:25 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-111137
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update libsmi to a version that fixes the described vulnerability.
- Review MIB files for crafted OCTET STRING values.
- Limit processing of untrusted MIB data.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-111137.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-111137 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-111137
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-111137 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-111137 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 16, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-111137', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-10-16T16:28:04.914973Z'} -
New CVE Received by [email protected]
Oct. 15, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/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 Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H Added CWE CWE-787 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/111xxx/CVE-2026-111137.json">CVE-2026-111137</a> Added Reference https://github.com/amartin755/libsmi Added Reference https://github.com/amartin755/libsmi/blob/c58307210fe995ec419db976eb234aebc71a9216/lib/smi.c#L479-L566 Added Reference https://hackmd.io/@haind-pwn/libsmi-smivalueasstring-octetstring-defval-oob-write Added Reference https://www.vulncheck.com/advisories/libsmi-through-0.5.0-out-of-bounds-write-via-smivalueasstring-octet-string-defval