CVE-2026-78594 json
Improper Handling of Highly Compressed Data in APM Server Leading to Persistent Denial of Service
published 2026-09-02 2 mo ago modified 2026-09-03 2 mo ago also EUVD-2026-70058
- cvss
- 4.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 43%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- elastic apm_server 8.19.20, 9.4.5
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.9 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Elastic Apm Server
Classification
- Weakness
-
- CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)
References
-
discuss.elastic.co
/t/apm-server-8-19-20-9-4-5-9-5-1-security-update-esa-2026-152/390110
vendor-advisory, mitigation
Sources
- CVE List CVE-2026-78594
- NVD CVE-2026-78594
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.