How severe is CVE-2026-40343?

CVE-2026-40343 has a CVSS 3.x base score of 5.8, 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 low, and availability none.

Is CVE-2026-40343 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-40343?

CVE-2026-40343 primarily affects Free5gc. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-40343?

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

Does CVE-2026-40343 have an EU (EUVD) identifier?

Yes. CVE-2026-40343 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24555.

When was CVE-2026-40343 published?

CVE-2026-40343 was published on 2026-04-22 and last updated on 2026-06-17.

CVE-2026-40343

CVE-2026-40343 is a medium-severity vulnerability in Free5gc with a CVSS 3.x base score of 5.8. 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-754.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v4: 6.9
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24555
Weakness: CWE-754
Affected product: Free5gc
Published: 2026-04-22
Last modified: 2026-06-17

Description

free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.2, a fail-open request handling flaw in the UDR service causes the `/nudr-dr/v2/policy-data/subs-to-notify` POST handler to continue processing requests even after request body retrieval or deserialization errors. This may allow unintended creation of Policy Data notification subscriptions with invalid, empty, or partially processed input, depending on downstream processor behavior. As of time of publication, a patched version is not available.

Frequently asked questions

What is CVE-2026-40343?: free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.2, a fail-open request handling flaw in the UDR service causes the `/nudr-dr/v2/policy-data/subs-to-notify` POST handler to continue processing requests even after request body retrieval or deserialization errors. This may allow unintended creation of Policy Data notification subscriptions with invalid, empty, or partially processed input, depending on downstream processor behavior. As of time of publication, a patched version is not available.
How severe is CVE-2026-40343?: CVE-2026-40343 has a CVSS 3.x base score of 5.8, 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 low, and availability none.
Is CVE-2026-40343 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-40343?: CVE-2026-40343 primarily affects Free5gc. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-40343?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-40343 have an EU (EUVD) identifier?: Yes. CVE-2026-40343 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24555.
When was CVE-2026-40343 published?: CVE-2026-40343 was published on 2026-04-22 and last updated on 2026-06-17.

References

https://github.com/free5gc/free5gc/security/advisories/GHSA-jwch-w7wh-gqjm

Affected products (2)

cpe:2.3:a:free5gc:free5gc:*:*:*:*:*:*:*:*
cpe:2.3:a:free5gc:udr:*:*:*:*:*:go:*:*

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