CVE-2026-26457

Application crash via zero-length CoAP option

Published Aug 27, 2026 · Updated Aug 27, 2026

Null pointer dereference in ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5 allows attackers to crash an application via a zero-length CoAP option. The coap_dump_msg() function processes the empty option and dereferences a null pointer instead of rejecting or safely handling the invalid value. Exploitation requires an application to invoke this diagnostic function on an attacker-influenced CoAP message, and the demonstrated consequence is a crash of that process.

CVSS severityUnavailable
Unscored
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Null pointer dereference in ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5 allows attackers to crash an application via a zero-length CoAP option. The coap_dump_msg() function processes the empty option and dereferences a null pointer instead of rejecting or safely handling the invalid value. Exploitation requires an application to invoke this diagnostic function on an attacker-influenced CoAP message, and the demonstrated consequence is a crash of that process.

The record

CVE
CVE-2026-26457
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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