Medium severity · published Mar 27, 2026
CVE-2026-4988
Open5GS CCA Message smf_s6b denial of service
5.9
CVSS
0.6%
EPSS
No
On KEV
Description
A security flaw has been discovered in Open5GS 2.7.6. This issue affects the function smf_gx_cca_cb/smf_gy_cca_cb/smf_s6b of the component CCA Message Handler. The manipulation results in denial of service. The attack may be launched remotely. Attacks of this nature are highly complex. The exploitability is assessed as difficult. The exploit has been released to the public and may be used for attacks.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
Open5GS · Open5gs
2.7.6 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4988
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4988
Product
https://github.com/open5gs/open5gs/
Exploit
https://github.com/open5gs/open5gs/issues/4342
Issue Tracking
https://github.com/open5gs/open5gs/issues/4342#issue-4021772232
Permissions Required
https://vuldb.com/?ctiid.353875
Third Party Advisory
https://vuldb.com/?id.353875
Exploit
https://vuldb.com/?submit.771349
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