What’s Vulnerable › Vulnerabilities
CVE-2026-78594: Improper Handling of Highly Compressed Data in APM Server Leading to Persistent Denial of Service
- Severity: medium (CVSS 4.9 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-02 · updated 2026-09-03
- Weakness: CWE-409
Description
Improper Handling of Highly Compressed Data (CWE-409) in APM Server can lead to a persistent denial of service via Excessive Allocation (CAPEC-130). An authenticated user with write access to source map content could store specially crafted, highly compressed content that exhausts the memory available to APM Server when it is later processed, terminating the process. The condition recurs on every restart until the stored content is removed.
Affected products
- Elastic APM Server: from 8.0.0 before 8.19.20; from 9.0.0 before 9.4.5; 9.5.0 — fixed in 8.19.20, 9.4.5
How to fix
Upgrade to a fixed version: Elastic APM Server 8.19.20, 9.4.5. Check the vendor advisory for mitigations.
References
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