How severe is CVE-2026-1521?

CVE-2026-1521 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-1521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-1521?

CVE-2026-1521 affects Open5gs. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-1521?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-1521 have an EU (EUVD) identifier?

Yes. CVE-2026-1521 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4885.

When was CVE-2026-1521 published?

CVE-2026-1521 was published on 2026-01-28 and last updated on 2026-06-17.

CVE-2026-1521

CVE-2026-1521 is a medium-severity vulnerability in Open5gs with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-404.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
CVSS v4: 5.5
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-4885
Weakness: CWE-404
Affected product: Open5gs
Published: 2026-01-28
Last modified: 2026-06-17

Description

A security flaw has been discovered in Open5GS up to 2.7.6. This affects the function sgwc_s5c_handle_bearer_resource_failure_indication of the file src/sgwc/s5c-handler.c of the component SGWC. Performing a manipulation results in denial of service. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks. The patch is named 69b53add90a9479d7960b822fc60601d659c328b. It is recommended to apply a patch to fix this issue.

Frequently asked questions

What is CVE-2026-1521?: A security flaw has been discovered in Open5GS up to 2.7.6. This affects the function sgwc_s5c_handle_bearer_resource_failure_indication of the file src/sgwc/s5c-handler.c of the component SGWC. Performing a manipulation results in denial of service. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks. The patch is named 69b53add90a9479d7960b822fc60601d659c328b. It is recommended to apply a patch to fix this issue.
How severe is CVE-2026-1521?: CVE-2026-1521 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-1521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-1521?: CVE-2026-1521 affects Open5gs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-1521?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-1521 have an EU (EUVD) identifier?: Yes. CVE-2026-1521 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4885.
When was CVE-2026-1521 published?: CVE-2026-1521 was published on 2026-01-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:open5gs:open5gs:*:*:*:*:*:*:*:*

More vulnerabilities in Open5gs

CVE-2024-40130 — Critical (CVSS 9.8): open5gs v2.6.4 is vulnerable to Buffer Overflow. via /lib/core/abts.c.
CVE-2024-40129 — Critical (CVSS 9.8): Open5GS v2.6.4 is vulnerable to Buffer Overflow. via /lib/pfcp/context.c.
CVE-2021-28122 — Critical (CVSS 9.8): A request-validation issue was discovered in Open5GS 2.1.3 through 2.2.x before 2.2.1. The WebUI component allows an…
CVE-2021-25863 — High (CVSS 8.8): Open5GS 2.1.3 listens on 0.0.0.0:3000 and has a default password of 1423 for the admin account.
CVE-2024-24429 — High (CVSS 8.6): A reachable assertion in the nas_eps_send_emm_to_esm function of Open5GS <= 2.6.4 allows attackers to cause a Denial of…
CVE-2024-34235 — High (CVSS 8.6): Open5GS MME versions <= 2.6.4 contains an assertion that can be remotely triggered via a malformed ASN.1 packet over…

All CVEs affecting Open5gs →

Other CWE-404 vulnerabilities

CVE-2023-24444 — Critical (CVSS 9.8): Jenkins OpenID Plugin 2.4 and earlier does not invalidate the previous session on login.
CVE-2024-31611 — Critical (CVSS 9.1): SeaCMS 12.9 has a file deletion vulnerability via admin_template.php.
CVE-2018-8450 — High (CVSS 8.8): A remote code execution vulnerability exists when Windows Search handles objects in memory, aka "Windows Search Remote…
CVE-2026-11317 — High (CVSS 8.7): A denial of service security issue exists in the affected product. The security issue stems from a fault occurring when…
CVE-2022-25762 — High (CVSS 8.6): If a web application sends a WebSocket message concurrently with the WebSocket connection closing when running on…
CVE-2020-26070 — High (CVSS 8.6): A vulnerability in the ingress packet processing function of Cisco IOS XR Software for Cisco ASR 9000 Series…

Browse all CWE-404 vulnerabilities →