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TI-2026-74921 Aliases CVE-2026-111137

Out-of-bounds write in libsmi lets crafted MIBs corrupt memory

Priority MEDIUM 64CWE-787Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · Low · High
Fix status
Deferred Red Hat: fix deferred

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

libsmi through 0.5.0 contains an out-of-bounds write in smiValueAsString() in lib/smi.c, where hex rendering of OCTET STRING values overflows a fixed 1024-byte static buffer (CWE-787). A local user must process a crafted MIB file with a long OCTET STRING default value, which corrupts adjacent library globals and crashes smidump or other consumers. A public exploit is linked in the references.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00128 2nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Deferred Red Hat: fix deferred

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
amartin755libsmiup to 0.5.0—No fix listedCNA
  • libsmi Vendoramartin755 Affected up to 0.5.0 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for libsmi. Red Hat lists libsmi as affected without a fix in Red Hat Enterprise Linux 6 (no fix planned) and in Red Hat Enterprise Linux 7, 8, 9 and 10 (none available).

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-16 Threatist record created from CVE-2026-111137
  2. 2026-10-16 Priority changed: MEDIUM → LOW
  3. 2026-10-16 Affected versions changed · Red Hat
  4. 2026-10-16 CVSS score added · Red Hat
  5. 2026-10-16 CISA SSVC decision points changed
  6. 2026-10-16 Priority changed: LOW → MEDIUM

References

Exploit 1

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences