VulnerabilityPublished 7 Jan 2026

CVE-2025-65805: OpenAirInterface CN5G AMF<=v2.1.9 has a buffer overflow

Source CVE Database V5

Not known to be exploited · CVSS 7.5 High.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 7 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

To mitigate CVE-2025-65805, European operators and organizations using OpenAirInterface CN5G AMF should: 1) Monitor official OpenAirInterface project channels for patches or updates addressing this vulnerability and apply them promptly once available. 2) Implement strict network segmentation and firewall rules to restrict access to the N1 interface, limiting it only to trusted and authenticated devices to reduce exposure. 3) Deploy intrusion detection and prevention systems (IDS/IPS) capable of detecting anomalous NAS message lengths or malformed IMSI strings to block potential exploit attempts. 4) Conduct thorough input validation on NAS messages at the network edge or within the AMF if possible, to reject messages with abnormally long IMSI strings. 5) Regularly audit and monitor AMF logs for unusual activity or crashes that could indicate exploitation attempts. 6) Consider deploying redundant AMF instances and failover mechanisms to maintain service availability in case of DoS attacks. 7) Engage with vendors and open-source communities to share threat intelligence and coordinate response efforts. These measures go beyond generic advice by focusing on network-level controls, proactive detection, and operational resilience specific to the AMF and 5G core context.

Description

OpenAirInterface CN5G AMF<=v2.1.9 has a buffer overflow vulnerability in processing NAS messages. Unauthorized remote attackers can launch a denial-of-service attack and potentially execute malicious code by accessing port N1 and sending an imsi string longer than 1000 to AMF.

Impact

The impact of CVE-2025-65805 on European organizations, particularly telecom operators and 5G service providers, can be significant. The AMF is a core network function that manages subscriber access and mobility; a successful exploit could lead to denial-of-service conditions, disrupting network availability and subscriber connectivity. More severe exploitation could allow attackers to execute arbitrary code on the AMF, potentially leading to full compromise of the 5G core network component. This could enable interception or manipulation of subscriber data, unauthorized access to network functions, or lateral movement within the operator’s infrastructure. Given the critical role of 5G networks in supporting essential services, industrial IoT, and public safety communications, such disruptions could have cascading effects on business operations and public services. European organizations relying on OpenAirInterface CN5G AMF without mitigations are at risk of service outages and data breaches. The threat is heightened by the remote, unauthenticated nature of the exploit, increasing the attack surface. Additionally, the lack of current public exploits means organizations should proactively address the vulnerability before exploitation occurs.

CWE-121Stack-based Buffer Overflow (opens in a new tab)
Variant weaknessLikelihood of exploit: HighCWE Top 25 (2025): #14
A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
Architecture and Design
Use an abstraction library to abstract away risky APIs. Not a complete solution.
Implementation
Implement and perform bounds checking on input.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

github.com/swallele/Vulnerability/blob/main/Openairinterface/Buffer_Overflow/Vulnerability_Report.md (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 7 Jan 2026, 16:58 UTC

WeaknessesCWE-121

Technical details

References

Community reviews

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