{"id":"CVE-2026-4240","summary":"Open5GS CCA smf_s6b_sta_cb denial of service","details":"A vulnerability was determined in Open5GS up to 2.7.6. The affected element is the function smf_gx_cca_cb/smf_gy_cca_cb/smf_s6b_aaa_cb/smf_s6b_sta_cb of the component CCA Handler. This manipulation causes denial of service. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized. Upgrading to version 2.7.7 is sufficient to fix this issue. Patch name: 80eb484a6ab32968e755e628b70d1a9c64f012ec. Upgrading the affected component is recommended.","modified":"2026-08-12T16:25:14.764948Z","published":"2026-03-16T13:32:09.729Z","database_specific":{"cna_assigner":"VulDB","cwe_ids":["CWE-404"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/4xxx/CVE-2026-4240.json","unresolved_ranges":[{"extracted_events":[{"introduced":"2.7.3"},{"last_affected":"2.7.3"},{"introduced":"2.7.4"},{"last_affected":"2.7.4"}],"source":"AFFECTED_FIELD"}]},"references":[{"type":"WEB","url":"https://github.com/open5gs/open5gs/"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/4xxx/CVE-2026-4240.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-4240"},{"type":"ADVISORY","url":"https://vuldb.com/?id.351182"},{"type":"ADVISORY","url":"https://vuldb.com/?submit.771361"},{"type":"REPORT","url":"https://github.com/open5gs/open5gs/issues/4343"},{"type":"REPORT","url":"https://github.com/open5gs/open5gs/issues/4343#issue-4021871895"},{"type":"REPORT","url":"https://vuldb.com/?ctiid.351182"},{"type":"FIX","url":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec"},{"type":"FIX","url":"https://github.com/open5gs/open5gs/releases/tag/v2.7.7"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/open5gs/open5gs","events":[{"introduced":"0"},{"fixed":"318eeb49a7dcdff733dec60e02d9c60aefca2fb9"},{"fixed":"80eb484a6ab32968e755e628b70d1a9c64f012ec"}],"database_specific":{"source":["CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:open5gs:open5gs:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"2.7.7"}]}}],"versions":["2.7.0","2.7.1","2.7.2","2.7.5","2.7.6","v2.7.2","v2.7.1","v2.7.0","v2.6.6","v2.6.4","v2.6.3","v2.6.2","v2.6.1","v2.4.9","v2.4.8","v2.4.7","v2.4.5","v2.4.4","v2.4.3","v2.4.1","v2.4.0","v2.3.6","v2.3.2","v2.3.0","v2.2.9","v2.2.8","v2.2.7","v2.2.6","v2.2.1","v2.2.0","v2.1.7","v2.1.5","v2.1.4","v2.1.3","v2.1.1","v2.1.0","v2.0.22","v2.0.18","v2.0.0","v1.3.0","v1.2.4","v1.2.3","v1.2.2","v1.2.1","v1.2.0","v1.1.0","v1.0.0","v0.5.2","v0.5.1","v0.5.0","v0.4.4","v0.4.3","v0.4.2","v0.4.1","v0.3.10","v0.3.8","v0.3.6","v0.3.5","v0.3.4","v0.3.3","v0.3.2","v0.3.1","v0.3.0","v0.2.0","v0.1.1","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-4240.json","vanir_signatures_modified":"2026-08-12T16:25:14Z","vanir_signatures":[{"signature_type":"Line","signature_version":"v1","source":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec","target":{"file":"src/smf/gy-path.c"},"deprecated":false,"digest":{"line_hashes":["286832280686897877386663269906374356152","237047032260203517884579827715635620405","116524115645494846346800667577386580350","291154197191466349190884344106472321044","53099392610014375379891174915329441325"],"threshold":0.9},"id":"CVE-2026-4240-097f0c1e"},{"digest":{"function_hash":"130296096657943261152918749756700875650","length":4319},"id":"CVE-2026-4240-2f75c394","signature_type":"Function","signature_version":"v1","source":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec","target":{"file":"src/smf/s6b-path.c","function":"smf_s6b_sta_cb"},"deprecated":false},{"digest":{"function_hash":"92942622530081123800530463779408980798","length":4316},"id":"CVE-2026-4240-868baa39","signature_type":"Function","signature_version":"v1","source":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec","target":{"function":"smf_s6b_aaa_cb","file":"src/smf/s6b-path.c"},"deprecated":false},{"id":"CVE-2026-4240-9e3e4749","signature_type":"Function","signature_version":"v1","source":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec","target":{"file":"src/smf/gy-path.c","function":"smf_gy_cca_cb"},"deprecated":false,"digest":{"function_hash":"48066293071339186820413693103493647171","length":8508}},{"id":"CVE-2026-4240-b7b2fbba","signature_type":"Line","signature_version":"v1","source":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec","target":{"file":"src/smf/s6b-path.c"},"deprecated":false,"digest":{"line_hashes":["173173611972938205206480386988927771189","237047032260203517884579827715635620405","261541326721294318550410748630230460168","83047868071616557476164884720546196498","67408004420327051982254656160822854663","237047032260203517884579827715635620405","261541326721294318550410748630230460168","83047868071616557476164884720546196498","67408004420327051982254656160822854663"],"threshold":0.9}},{"digest":{"function_hash":"110292961675724856263265827935457661500","length":10609},"id":"CVE-2026-4240-c19707cc","signature_type":"Function","signature_version":"v1","source":"https://github.com/open5gs/open5gs/commit/80eb484a6ab32968e755e628b70d1a9c64f012ec","target":{"file":"src/smf/gx-path.c","function":"smf_gx_cca_cb"},"deprecated":false},{"id":"CVE-2026-4240-d237e515","signature_type":"Line","signature_version":"v1","sour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