How severe is CVE-2023-37020?

CVE-2023-37020 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-37020 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-37020?

CVE-2023-37020 affects Open5gs. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-37020?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2023-37020 have an EU (EUVD) identifier?

Yes. CVE-2023-37020 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-40940.

When was CVE-2023-37020 published?

CVE-2023-37020 was published on 2025-01-22 and last updated on 2026-06-17.

CVE-2023-37020

CVE-2023-37020 is a high-severity vulnerability in Open5gs with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-617.

Key facts

Severity: High (CVSS 3.x base score 8.6)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-40940
Weakness: CWE-617
Affected product: Open5gs
Published: 2025-01-22
Last modified: 2026-06-17

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 Release Complete` message missing a required `MME_UE_S1AP_ID` field to repeatedly crash the MME, resulting in denial of service.

Frequently asked questions

What is CVE-2023-37020?: 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 Release Complete` message missing a required `MME_UE_S1AP_ID` field to repeatedly crash the MME, resulting in denial of service.
How severe is CVE-2023-37020?: CVE-2023-37020 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-37020 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-37020?: CVE-2023-37020 affects Open5gs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-37020?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2023-37020 have an EU (EUVD) identifier?: Yes. CVE-2023-37020 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-40940.
When was CVE-2023-37020 published?: CVE-2023-37020 was published on 2025-01-22 and last updated on 2026-06-17.

References

https://cellularsecurity.org/ransacked

Affected products (1)

cpe:2.3:a:open5gs:open5gs:*:*:*:*:*:*:*:*

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