Apache Kylin: Unsafe Java deserialization via external cache service
Summary
Apache Kylin, an OLAP engine for big-data analytics, contains an unsafe Java deserialization flaw (CWE-502) in versions 4.0.0 through 5.0.4. According to the CNA, unsafe deserialization can occur when the external cache service is broken or supplies untrusted data, so an attacker who can tamper with the cache may be able to affect the Kylin host. The CVSS v3.1 base score is 9.8 (critical) with high impact on confidentiality, integrity and availability; the CNA's SSVC rates technical impact as total and automatable as yes. Exposure depends mainly on whether the cache backend is reachable from untrusted networks.
Affected
- Apache Kylin 4.0.0 through 5.0.4
Fixed in
- Apache Kylin 5.0.5 (vendor-confirmed fix)
Workaround
- Unknown. No vendor workaround found for this CVE.
- Own suggestion, not from the vendor: restrict network access to the cache service so that only Kylin hosts can reach it, enable authentication and TLS on the cache, and limit who can write to it.
Exploitation
- No known exploitation as of the sources checked.
- No public proof of concept found.
- Not listed in the CISA KEV catalogue.
- CISA SSVC: exploitation none, automatable yes, technical impact total.
Our recommendation
- Check whether Apache Kylin 4.x or 5.0.0 to 5.0.4 is in use, for example in data-platform environments.
- Plan and apply the upgrade to Apache Kylin 5.0.5.
- Until the upgrade is done, isolate Kylin hosts and their cache backend and make sure the cache is not reachable from untrusted networks.
- Monitor the cache service for unexpected access or changes to data.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Apache mailing list thread (CVE-2026-64610) lists.apache.org
- oss-security post CVE-2026-64610 www.openwall.com
- PT Security advisory PT-2026-115602 vulners.com
- PSIRT aggregator CVE-2026-64610 psirt.com
- CVE Brief archive 2026/10/22 cvebrief.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 30 Oct 2026, 17:41.
Original description (NVD)
Deserialization of Untrusted Data vulnerability in Apache Kylin. Unsafe Java deserialization could happen from a broken external cache service. This issue affects Apache Kylin: from 4 through 5.0.4. Users are recommended to upgrade to version 5.0.5, which fixes the issue.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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