CVE-2025-55039

Description

This issue affects Apache Spark versions before 3.4.4, 3.5.2 and 4.0.0. Apache Spark versions before 4.0.0, 3.5.2 and 3.4.4 use an insecure default network encryption cipher for RPC communication between nodes. When spark.network.crypto.enabled is set to true (it is set to false by default), but spark.network.crypto.cipher is not explicitly configured, Spark defaults to AES in CTR mode (AES/CTR/NoPadding), which provides encryption without authentication. This vulnerability allows a man-in-the-middle attacker to modify encrypted RPC traffic undetected by flipping bits in ciphertext, potentially compromising heartbeat messages or application data and affecting the integrity of Spark workflows. To mitigate this issue, users should either configure spark.network.crypto.cipher to AES/GCM/NoPadding to enable authenticated encryption or enable SSL encryption by setting spark.ssl.enabled to true, which provides stronger transport security.

How to fix CVE-2025-55039

To remediate CVE-2025-55039, upgrade the affected package to a fixed version below.

• —upgrade to 3.4.4 or later
• —upgrade to 3.5.2 or later
• —upgrade to 3.4.4 or later
• —upgrade to 3.4.4 or later

Is CVE-2025-55039 being exploited?

Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.

Affected packages (4)

• from 0, < 3.4.4
• >= 3.5.0, < 3.5.2
• from 0, < 3.4.4
• from 0, < 3.4.4, >= 3.5.0, < 3.5.2

CVSS scores

References (10)

• ADVISORYgithub.com/advisories/GHSA-6p6v-m64v-jx8q
• ADVISORYlists.apache.org/thread/zrgyy9l85nm2c7vk36vr7bkyorg3w4qq
• ADVISORYnvd.nist.gov/vuln/detail/CVE-2025-55039
• PATCHgithub.com/apache/spark
• WEB