Cyber Posture

CVE-2023-37016

HighPublic PoC

Published: 22 January 2025

Published
22 January 2025
Modified
22 April 2025
KEV Added
Patch
CVSS Score 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0031 53.7th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-37016 is a high-severity Reachable Assertion (CWE-617) vulnerability in Open5Gs Open5Gs. Its CVSS base score is 8.6 (High).

Operationally, ranked in the top 46.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SC-5 (Denial-of-service Protection) and SI-10 (Information Input Validation).

Threat & Defense at a Glance

What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly remediates the software flaw causing assertion failure in Open5GS MME from malformed S1AP packets by monitoring vulnerabilities and applying patches.

preventdetect

Protects against denial-of-service by limiting effects of repeated MME crashes triggered by malformed UE Context Modification Response packets.

prevent

Validates content of incoming S1AP ASN.1 packets to reject malformed messages missing required fields like MME_UE_S1AP_ID.

NVD Description

Open5GS MME versions <= 2.6.4 contain an assertion that can be remotely triggered via a malformed ASN.1 packet over the S1AP interface. An attacker may send a `UE Context Modification Response` message missing a required `MME_UE_S1AP_ID` field to repeatedly crash…

more

the MME, resulting in denial of service.

Deeper analysisAI

CVE-2023-37016 affects Open5GS Mobility Management Entity (MME) versions up to and including 2.6.4. The vulnerability stems from an assertion failure triggered by a malformed ASN.1 packet over the S1AP interface. Specifically, an attacker can send a UE Context Modification Response message lacking the required MME_UE_S1AP_ID field, causing the MME process to crash. This issue is classified under CWE-617 (Reachable Assertion) and carries a CVSS v3.1 base score of 8.6 (AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H), indicating high severity due to its network accessibility, low complexity, and scope change.

Any unauthenticated remote attacker with network access to the S1AP interface can exploit this vulnerability. By repeatedly transmitting the malformed UE Context Modification Response, the attacker can crash the MME process multiple times, leading to a denial-of-service condition that disrupts core network functions for user equipment context management.

Mitigation details are available in the advisory published at https://cellularsecurity.org/ransacked.

Details

CWE(s)

Affected Products

open5gs
open5gs
≤ 2.6.4

CVEs Like This One

CVE-2025-15530Same product: Open5Gs Open5Gs
CVE-2023-37018Same product: Open5Gs Open5Gs
CVE-2024-24428Same product: Open5Gs Open5Gs
CVE-2024-34235Same product: Open5Gs Open5Gs
CVE-2023-37019Same product: Open5Gs Open5Gs
CVE-2023-37021Same product: Open5Gs Open5Gs
CVE-2026-2523Same product: Open5Gs Open5Gs
CVE-2024-24430Same product: Open5Gs Open5Gs
CVE-2023-37017Same product: Open5Gs Open5Gs
CVE-2024-24427Same product: Open5Gs Open5Gs

References