SB2026110728 - Multiple vulnerabilities in Oracle Communications Cloud Native Core Service Communication Proxy

Description

This security bulletin contains information about 7 vulnerabilities.

1) Input validation error (CVE-ID: CVE-2026-27135)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to missing state validation in the nghttp2 session handling logic when processing malformed frames after session termination has been initiated. A remote attacker can send specially crafted frames to cause a denial of service.

For PRIORITY_UPDATE and ALTSVC frames, the affected extension types must be explicitly enabled. Builds with assertions disabled may not crash under the same conditions.

2) Improper Encoding or Escaping of Output (CVE-ID: CVE-2026-34481)

CWE-ID: CWE-116 - Improper Encoding or Escaping of Output

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause downstream log processing systems to reject or fail to index affected records.

The vulnerability exists due to improper serialization of non-finite floating-point values in JsonTemplateLayout when processing log events containing a MapMessage with an attacker-controlled floating-point value. A remote attacker can supply a non-finite floating-point value to cause downstream log processing systems to reject or fail to index affected records.

Exploitation is possible only if the application uses JsonTemplateLayout and logs a MapMessage containing the attacker-controlled value.

3) Improper handling of highly compressed data (CVE-ID: CVE-2026-21441)

CWE-ID: CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to the application does not properly handle highly compressed data when sending HTTP redirect responses. A remote attacker can multiple large requests to the application, consume all available CPU and memory resources and perform a denial of service attack.

4) Improper access control (CVE-ID: CVE-2025-14821)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to manipulate trusted SSH configuration and host key data to compromise connection security.

The vulnerability exists due to improper access control in the global configuration file loading behavior on Windows when loading configuration files and ssh_known_hosts from the C:etc directory. A local user can create attacker-controlled files in that directory to manipulate trusted SSH configuration and host key data to compromise connection security.

This issue occurs when libssh is built with default configure options on Windows.

5) Improper input validation (CVE-ID: CVE-2025-8837)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local authenticated user to execute arbitrary code.

The vulnerability exists due to improper input validation within the ATS Framework (JasPer) component in Oracle Communications Cloud Native Core Service Communication Proxy. A local authenticated user can exploit this vulnerability to execute arbitrary code.

6) Deserialization of Untrusted Data (CVE-ID: CVE-2026-41855)

CWE-ID: CWE-502 - Deserialization of Untrusted Data

CVSSv4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to perform unauthorized actions.

The vulnerability exists due to unsafe deserialization in org.springframework.jms.support.converter.MappingJackson2MessageConverter and org.springframework.jms.support.converter.JacksonJsonMessageConverter when processing messages in an untrusted JMS environment. A remote attacker can send a crafted message to perform unauthorized actions.

Exploitation can lead to arbitrary class instantiation through gadget class deserialization.

7) Improper input validation (CVE-ID: CVE-2026-33557)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

The vulnerability exists due to improper input validation within the Message Bus (Apache Kafka) component in Oracle Communications Unified Assurance. A remote non-authenticated attacker can exploit this vulnerability to read and manipulate data.

Remediation

Install update from vendor's website.

References

• https://www.oracle.com/security-alerts/cpujul2026.html