CVE-2021-41794

Name: CVE-2021-41794
Creator: NVD / NIST
Published: 2021-10-07T15:15:11.2+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.18%

Last modified Jun 17, 2026

CVE-2021-41794 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. ogs_fqdn_parse in Open5GS 1.0.0 through 2.3.3 inappropriately trusts a client-supplied length value, leading to a buffer overflow. The attacker can send a PFCP Session Establishment Request with "internet" as the PDI Network Instance. EPSS estimates a 1.18% chance of exploitation in the next 30 days.

Description

ogs_fqdn_parse in Open5GS 1.0.0 through 2.3.3 inappropriately trusts a client-supplied length value, leading to a buffer overflow. The attacker can send a PFCP Session Establishment Request with "internet" as the PDI Network Instance. The first character is interpreted as a length value to be used in a memcpy call. The destination buffer is only 100 bytes long on the stack. Then, 'i' gets interpreted as 105 bytes to copy from the source buffer to the destination buffer.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.18%

63.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Open5gs	Open5gs	>= 1.0.0, <= 2.3.3

References

https://research.nccgroup.com/2021/10/06/technical-advisory-open5gs-stack-buffer-overflow-during-pfcp-session-establishment-on-upf-cve-2021-41794Exploit, Third Party Advisory
https://research.nccgroup.com/2021/10/06/technical-advisory-open5gs-stack-buffer-overflow-during-pfcp-session-establishment-on-upf-cve-2021-41794Exploit, Third Party Advisory

Timeline

Published: Oct 7, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-41794?

How severe is CVE-2021-41794?

CVE-2021-41794 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.18% probability of exploitation in the next 30 days.

How do I fix CVE-2021-41794?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-41794?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST