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UK Cyber Defence
VulnerabilityAnalyzed

CVE-2023-37016

Open5GS MME versions <= 2.6.4 contain an assertion that can be remotely triggered via a malformed ASN.1 packet over the S1AP interface.

HIGH 8.6EPSS 0.78%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.78%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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 the MME, resulting in denial of service.

CVSS 3.1
8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS
0.78% probability · 56th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-617
Affected
open5gs/open5gs
Source
cve@mitre.org
EPSS trend
0%3%5%26 October 2026: 0.78%26 October 202626 October 2026

EPSS 0.8% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.