What is the CVSS score of CVE-2021-41794?

CVE-2021-41794 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 1.2%.

Is there a public PoC exploit available for CVE-2021-41794?

Yes, a public proof-of-concept exploit is available for CVE-2021-41794. Prioritise patching immediately. EPSS: 1.2%.

Open5gs CVE-2021-41794

HIGH

Classic Buffer Overflow (CWE-120)

2021-10-07 cve@mitre.org

Buffer Overflow Open5gs

7.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.5 HIGH

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

CVE Published

Oct 07, 2021 - 15:15 nvd

HIGH 7.5

DescriptionNVD

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.

AnalysisAI

ogs_fqdn_parse in Open5GS 1.0.0 through 2.3.3 inappropriately trusts a client-supplied length value, leading to a buffer overflow. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified as Buffer Copy without Size Check (CWE-120), which allows attackers to overflow a buffer to corrupt adjacent memory. 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. Affected products include: Open5Gs. Version information: through 2.3.3.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Always validate buffer sizes before copy operations. Use bounded functions (strncpy, snprintf). Enable compiler protections.