CVE-2026-66859Public exploitNetwork attack vectorHinoki check available

Service crash via missing multiplexed message name

Published Oct 2, 2026 · Updated Oct 2, 2026

NULL pointer dereference in Apache Thrift c_glib multiplexed processing before 0.25.0 allows attackers to crash a service with a nameless message. The thrift_multiplexed_processor_process_impl function passes a missing method name to strtok_r after a successful header read, leaving its token state uninitialized. The crash requires a protocol that reports success without supplying a name; Apache states that the standard binary and compact protocols supply one.

CVSS severity8.7
High
EPSS probability0.43%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

NULL pointer dereference in Apache Thrift c_glib multiplexed processing before 0.25.0 allows attackers to crash a service with a nameless message. The thrift_multiplexed_processor_process_impl function passes a missing method name to strtok_r after a successful header read, leaving its token state uninitialized. The crash requires a protocol that reports success without supplying a name; Apache states that the standard binary and compact protocols supply one.

The record

CVE
CVE-2026-66859
Published
Oct 2, 2026
Updated
Oct 2, 2026
Vendor
Apache Software Foundation
Product
Apache Thrift
Classifications
CWE-457, CWE-476, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 2, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <0.25.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apache Software Foundation · Apache Thriftversion=0 <0.25.0

Published CVSS scores

8.7Apache Software FoundationCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-457Use of Uninitialized Variable
CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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