Cyber Resilience

CVE-2026-2521

Memory Safety in Open5Gs ≤ 2.7.6

Public PoCMemory Safety
Published
15 February 2026
Modified
18 February 2026
Patch / advisory
View advisory
CVSS Score v4 5.5
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0068 49th percentile
Risk Priority 40 floored blend · peak EPSS

Summary

CVE-2026-2521 is a medium-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Open5Gs Open5Gs. Its CVSS base score is 5.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Process Injection (T1055); ranked at the 49th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-8 (Security and Privacy Engineering Principles) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-2521 is a memory corruption vulnerability (CWE-119) in Open5GS versions up to and including 2.7.6. The issue resides in the sgwc_s5c_handle_create_session_response function within the SGW-C component. It has a CVSS v3.1 base score of 5.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L), indicating medium severity primarily due to its potential for remote denial-of-service impacts.

The vulnerability can be exploited remotely by unauthenticated attackers with low complexity and no user interaction required. Successful exploitation triggers memory corruption, resulting in limited availability disruption, such as crashes or service degradation in the affected SGW-C process. A public exploit is available, enabling potential attacks against exposed Open5GS deployments.

References, including GitHub issues #4282 and related comments in the open5gs/open5gs repository, indicate the project was notified early via an issue report but has not yet responded or issued patches. VulDB entries (ctiid.346109 and id.346109) document the flaw but provide no additional mitigation guidance.

Notable context includes the public availability of an exploit, which could facilitate real-world attacks on unpatched 5G core network implementations using Open5GS. No evidence of active exploitation in the wild is reported.

EU & UK References

Vulnerability Data

A weakness has been identified in Open5GS up to 2.7.6. This issue affects the function sgwc_s5c_handle_create_session_response of the component SGW-C. Executing a manipulation can lead to memory corruption. The attack may be performed from remote. The exploit has been made…

more

available to the public and could be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.

CWE(s)
CWE-119

Related Threats

MITRE ATT&CK Enterprise Techniques

T1055 Process Injection Stealth
Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-2522Same product: Open5Gs Open5Gs
CVE-2026-8746Same product: Open5Gs Open5Gs
CVE-2026-8186Same product: Open5Gs Open5Gs
CVE-2025-15555Same product: Open5Gs Open5Gs
CVE-2024-34476Same product: Open5Gs Open5Gs
CVE-2025-44951Same product: Open5Gs Open5Gs
CVE-2025-44952Same product: Open5Gs Open5Gs
CVE-2024-40129Same product: Open5Gs Open5Gs
CVE-2024-40130Same product: Open5Gs Open5Gs
CVE-2025-29646Same product: Open5Gs Open5Gs

Affected Assets

open5gs
open5gs
≤ 2.7.6

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

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Validate
Prove the fix (OWASP ASVS)
  • V17.3.2

Mitigating Controls (NIST 800-53 r5) AI

SA-8 Security and Privacy Engineering Principles partial match

Secure engineering principles require memory-safe design and coding that structurally avoids buffer-boundary violations.

SI-10 Information Input Validation partial match

Input validation directly enforces bounds checking that stops out-of-bounds reads/writes from being introduced or reached.

SI-16 Memory Protection partial match

Memory protection restricts exploitation impact of buffer overflows without eliminating the underlying coding flaw.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (bounds checking, safe APIs, reviews) directly prevent this class of flaw.

ID.RA-01 partial match
prevents

Vulnerability scanning and code analysis directly surface buffer-boundary flaws.

ID.RA-08 partial match
prevents

Receiving and triaging vulnerability disclosures commonly includes buffer-related reports.

PR.AT-02 partial match
prevents

Developer training on secure coding reduces introduction of memory-buffer errors.

PR.PS-02 partial match
prevents

Patching replaces vulnerable code containing buffer-boundary defects.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches out-of-bounds accesses before release, covering most instances of the weakness.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle mandates memory-safety practices that directly prevent buffer-boundary violations.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify memory-safety rules, but do not prescribe implementation details.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture and engineering principles include memory-safe design patterns that mitigate buffer overflows.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid unsafe buffer operations, directly eliminating CWE-119.

References