CVE-2025-27817 | Apache Kafka Client: Arbitrary file read and SSRF vulnerability

A possible arbitrary file read and SSRF vulnerability has been identified in Apache Kafka Client. Apache Kafka Clients accept configuration data for setting the SASL/OAUTHBEARER connection with the brokers, including "sasl.oauthbearer.token.endpoint.url" and "sasl.oauthbearer.jwks.endpoint.url". Apache Kafka allows clients to read an arbitrary file and return the content in the error log, or sending requests to an unintended location. In applications where Apache Kafka Clients configurations can be specified by an untrusted party, attackers may use the "sasl.oauthbearer.token.endpoint.url" and "sasl.oauthbearer.jwks.endpoint.url" configuratin to read arbitrary contents of the disk and environment variables or make requests to an unintended location. In particular, this flaw may be used in Apache Kafka Connect to escalate from REST API access to filesystem/environment/URL access, which may be undesirable in certain environments, including SaaS products. Since Apache Kafka 3.9.1/4.0.0, we have added a system property ("-Dorg.apache.kafka.sasl.oauthbearer.allowed.urls") to set the allowed urls in SASL JAAS configuration. In 3.9.1, it accepts all urls by default for backward compatibility. However in 4.0.0 and newer, the default value is empty list and users have to set the allowed urls explicitly.

Published: 2025-06-10 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-27817 is rated High Risk (66.2/100): CVSS High severity, with high exploitation likelihood (EPSS 62.37%, 99th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +1.53% over the last day, indicating growing attacker interest. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-27817

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-30 60.84% 62.37% +1.53%
2 2026-06-15 19.10% 60.84% +41.75%
3 2026-06-14 19.10%

Full EPSS history (27 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-27817

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-27817

GitHub Security Advisory for CVE-2025-27817

GHSA-vgq5-3255-v292 · Severity: medium · Ecosystem: maven — Apache Kafka Client Arbitrary File Read and Server Side Request Forgery Vulnerability

OS Trackers for CVE-2025-27817

vendor priority summary link
redhat high https://access.redhat.com/security/cve/CVE-2025-27817

Affected software / configurations for CVE-2025-27817

Vendor Product Version Raw CPE
apache kafka >= 3.1.0, < 3.9.1 cpe:2.3:a:apache:kafka:*:*:*:*:*:*:*:*

References for CVE-2025-27817

URL Tags
https://kafka.apache.org/cve-list Vendor Advisory
http://www.openwall.com/lists/oss-security/2025/06/09/1 Mailing List Third Party Advisory
cvelogic Threat Intelligence