{"id":"CVE-2026-68155","revision":"d4baafa6cba248e4aadb6d8505071fc9","records":[{"revision":"d4baafa6cba248e4aadb6d8505071fc9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-68155","aliases":[],"title":"libceph: Reject monmaps advertising zero monitors","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Reject monmaps advertising zero monitors\n\nA message of type CEPH_MSG_MON_MAP contains a monmap that is sent from a\nmonitor to the client. This monmap contains information about the\nexisting monitors in the cluster. Currently, a monmap indicating that\nthere are zero monitors in the cluster is treated as valid. However, it\nis impossible to have zero monitors in the cluster and still receive a\nvalid monmap from a monitor. Therefore, such a monmap must be corrupted\nand should be treated as invalid. Furthermore, a monmap with a monitor\ncount of zero can subsequently crash the client when attempting to open\na session with a monitor in __open_session(). This happens because the\n\"BUG_ON(monc->monmap->num_mon < 1)\" assertion in pick_new_mon() is\ntriggered.\n\nThis patch extends a check in ceph_monmap_decode() to also reject\narriving mon_maps with num_mon == 0 rather than only with\nnum_mon > CEPH_MAX_MON.\n\n[ idryomov: drop \"log output for unusual values of num_mon\" part ]","state":0,"publishedAt":"2026-08-10T11:59:21.2+00:00","modifiedAt":"2026-10-19T20:58:54.643+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ceph/mon_client.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"ba5f0015bfd376d764163045a61c17be75f44dae\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"caf082ef8609a6ac26159ce115f55ab7d00231a3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"e3ccd4ecab09b22f507f49cb7ed9990c7158ceab\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"0591a15815b498be628a937146e44487d599ba33\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"cd0d41bc569632eaaeccde9d2a6bc919ec00c407\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"e67e8b694872c9bc66996040f9de9242f6236ed9\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"3b249546f59c3d6d3592c10657f82bc3f1faa07c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"ba75bb98cfb93b62c54af25bf67ff90857264bbe\",\n                            \"lessThan\": \"40480eee361ed9676b3f844d532ac28b47251634\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ceph/mon_client.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.34\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.34\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.271\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.216\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.183\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.148\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.101\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.42\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.6\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/ba5f0015bfd376d764163045a61c17be75f44dae","https://git.kernel.org/stable/c/caf082ef8609a6ac26159ce115f55ab7d00231a3","https://git.kernel.org/stable/c/e3ccd4ecab09b22f507f49cb7ed9990c7158ceab","https://git.kernel.org/stable/c/0591a15815b498be628a937146e44487d599ba33","https://git.kernel.org/stable/c/cd0d41bc569632eaaeccde9d2a6bc919ec00c407","https://git.kernel.org/stable/c/e67e8b694872c9bc66996040f9de9242f6236ed9","https://git.kernel.org/stable/c/3b249546f59c3d6d3592c10657f82bc3f1faa07c","https://git.kernel.org/stable/c/40480eee361ed9676b3f844d532ac28b47251634"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68155","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-68155","identifiers":["CVE-2026-68155"]},"retained":false,"historicalAffected":[]}],"coverage":[]}