CVE-2021-44081Public exploitNetwork attack vector

AMF service crash via unchecked SUPI length

Published Mar 29, 2022 · Updated Aug 4, 2024

Buffer overflow in the Open5GS 2.1.4 AMF allows remote attackers to crash the service with an oversized MSIN in a SUPI. The initialUEMessage path allocates a fixed 15-digit OGS_MAX_IMSI_BCD_LEN stack buffer but does not validate the SUPI length before copying it. Network access to the initial UE registration path is sufficient; the resulting stack corruption terminates the AMF and interrupts its service.

CVSS severity7.5
High
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in the Open5GS 2.1.4 AMF allows remote attackers to crash the service with an oversized MSIN in a SUPI. The initialUEMessage path allocates a fixed 15-digit OGS_MAX_IMSI_BCD_LEN stack buffer but does not validate the SUPI length before copying it. Network access to the initial UE registration path is sufficient; the resulting stack corruption terminates the AMF and interrupts its service.

The record

CVE
CVE-2021-44081
Published
Mar 29, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 29, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499.004Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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