OpenSearch Data Prepper plugins trust all SSL certificates by default

Description

Impact

The OpenSearch sink and source plugins in Data Prepper are configured to trust all SSL certificates by default when no certificate path was provided, making connections vulnerable to man-in-the-middle attacks.

Prior to this fix, the OpenSearch sink and source plugins would automatically use a trust all SSL strategy when connecting to OpenSearch clusters if no certificate path was explicitly configured. This behavior bypassed SSL certificate validation, potentially allowing attackers to intercept and modify data in transit through man-in-the-middle attacks.

The vulnerability affects connections to OpenSearch when the cert parameter is not explicitly provided.

Patches

Data Prepper 2.12.2

Workarounds

If you cannot immediately upgrade to the fixed version, you can implement the following workaround.

OpenSearch sink

Add the cert parameter to your OpenSearch sink configuration with the path to your cluster's CA certificate. The following example shows how to accomplish this.

sink:
  - opensearch:
      hosts: ["https://your-opensearch-cluster:9200"]
      cert: /path/to/your/ca-certificate.pem

OpenSearch source

Add the cert parameter to your OpenSearch sink configuration with the path to your cluster's CA certificate. The following example shows how to accomplish this.

sink:
  - opensearch:
      hosts: ["https://your-opensearch-cluster:9200"]
      connection:
        cert: /path/to/your/ca-certificate.pem

References

N/A

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2025-10-15 20:09:53 UTC
Updated
2025-10-15 20:09:53 UTC
GitHub reviewed
2025-10-15 20:09:53 UTC
NVD published
2025-10-15

EPSS Score

Score Percentile
0.02% 5.20%

CVSS Scores

Base score Version Severity Vector
7.4 3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-295 Improper Certificate Validation

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
maven org.opensearch.dataprepper.plugins:opensearch < 2.12.2 2.12.2

References

cvelogic Threat Intelligence