Elastic APM Server up to 8.19.19/9.4.4/9.5.0 data amplification

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
3.7$0-$5k1.89+

Summaryinfo

A vulnerability was found in Elastic APM Server up to 8.19.19/9.4.4/9.5.0. It has been classified as problematic. Affected by this issue is some unknown functionality. This manipulation causes data amplification. The identification of this vulnerability is CVE-2026-78594. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic was found in Elastic APM Server up to 8.19.19/9.4.4/9.5.0. Affected by this vulnerability is an unknown code block. The manipulation with an unknown input leads to a data amplification vulnerability. The CWE definition for the vulnerability is CWE-409. The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output. As an impact it is known to affect availability. The summary by CVE is:

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.

It is possible to read the advisory at discuss.elastic.co. This vulnerability is known as CVE-2026-78594 since 08/24/2026. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 8.19.20, 9.4.5 or 9.5.1 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.8
VulDB Meta Temp Score: 3.7

VulDB Base Score: 2.7
VulDB Temp Score: 2.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.9
CNA Vector (elastic): 🔒

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Data amplification
CWE: CWE-409 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: APM Server 8.19.20/9.4.5/9.5.1

Timelineinfo

08/24/2026 CVE reserved
09/02/2026 +9 days Advisory disclosed
09/02/2026 +0 days VulDB entry created
09/02/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: discuss.elastic.co
Status: Confirmed

CVE: CVE-2026-78594 (🔒)
GCVE (CVE): GCVE-0-2026-78594
GCVE (VulDB): GCVE-100-398179

Entryinfo

Created: 09/02/2026 17:03
Changes: 09/02/2026 17:03 (62)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you need the next level of professionalism?

Upgrade your account now!