{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-68159", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-30T09:28:09.371Z", "datePublished": "2026-08-10T11:59:25.697Z", "dateUpdated": "2026-08-23T12:46:00.131Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-23T12:46:00.131Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: bound pg_{temp,upmap,upmap_items} length to CEPH_PG_MAX_SIZE\n\n__decode_pg_temp() decodes an user-controlled length but only rejects\nvalues large enough to overflow the allocation; it does not bound it to\nCEPH_PG_MAX_SIZE. The helper backs both pg_temp and pg_upmap decoding, and\napply_upmap()/get_temp_osds() later copy the decoded list into the fixed-size\non-stack array struct ceph_osds.osds[CEPH_PG_MAX_SIZE]. A monitor that sends\nan OSDMap with a pg_temp/pg_upmap entry longer than 32 thus causes a stack\nout-of-bounds write.\n\nAn OSD set for a single PG can never exceed CEPH_PG_MAX_SIZE, so reject longer\nentries at decode time. The bound is well below the old overflow threshold, so\nit also covers the allocation-size overflow the previous check guarded against.\n\n BUG: KASAN: stack-out-of-bounds in ceph_pg_to_up_acting_osds\n Write of size 4 ... by task exploit\n kasan_report (mm/kasan/report.c:595)\n ceph_pg_to_up_acting_osds (net/ceph/osdmap.c:2617 net/ceph/osdmap.c:2833)\n calc_target (net/ceph/osd_client.c:1638)\n __submit_request (net/ceph/osd_client.c:2394)\n ceph_osdc_start_request (net/ceph/osd_client.c:2490)\n ceph_osdc_call (net/ceph/osd_client.c:5164)\n rbd_dev_image_probe (drivers/block/rbd.c:6899)\n do_rbd_add (drivers/block/rbd.c:7138)\n ...\n kernel BUG at net/ceph/osdmap.c:2670!\n\n[ idryomov: do the same in __decode_pg_upmap_items() ]" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - Malicious pg_temp/pg_upmap data arrives in CEPH_MSG_OSD_MAP from a Ceph monitor or OSD over TCP, is decoded in libceph, and later triggers stack corruption in ceph_pg_to_up_acting_osds during RBD/CephFS/libceph client I/O.\nAC:L - A compromised or attacker-controlled monitor can publish osdmap entries with length >32 for chosen PGs; once the client subscribes, kernel I/O paths such as RBD mount/probe via calc_target deterministically invoke apply_upmap/get_temp_osds and overflow the stack buffer.\nPR:N - Exploitation requires no privileges on the victim host; any machine acting as a Ceph client that receives a forged osdmap from a cluster peer over the network can be attacked without local user capabilities or namespace tricks.\nUI:N - No victim user action is needed during exploitation beyond the host already being a Ceph client; forged osdmaps are applied automatically and the overflow fires on subsequent kernel client operations without interactive steps.\nS:U - Impact is confined to kernel memory on the Ceph client host (privilege escalation or crash); it does not cross VM, IOMMU, or sandbox boundaries to other security authorities.\nC:H - KASAN-confirmed stack out-of-bounds write in ceph_pg_to_up_acting_osds corrupts adjacent stack memory and can be leveraged for arbitrary kernel memory disclosure, not merely a bounded leak.\nI:H - Unbounded copy loops in apply_upmap() and get_temp_osds() write attacker-controlled u32 OSD IDs past the fixed osds[CEPH_PG_MAX_SIZE] stack array, enabling control-flow hijack and arbitrary kernel writes.\nA:H - The reported reproducer triggers KASAN stack-out-of-bounds followed by kernel BUG in ceph_pg_to_up_acting_osds, demonstrating a reliable kernel oops or panic from malformed osdmap processing on Ceph clients." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ceph/osdmap.c" ], "versions": [ { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "66eec4af1e080b695229c9a20635648a6d12fedf", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "4daf06456677177f2a6044729abac59c1b49e87b", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "d5650ddbd4d42c1a916c8fe1a4c4cb573ef810a1", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "42bc06c67d94d5f2a6b33294b0c4b07d8a47c515", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "ebdf4b4f3b1474079980a2e5cd79ad65fb54db57", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "590b07ceea138d49c9b64f65d263aa902d3b4730", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "e36663145abd7024f0281dfb22fdef65f185845b", "status": "affected", "versionType": "git" }, { "version": "a303bb0e58345fe9f7ab2f82b90266f2b5036058", "lessThan": "9f00f9cf2be293efe899db67dc5272e3a9c62717", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/ceph/osdmap.c" ], "versions": [ { "version": "4.13", "status": "affected" }, { "version": "0", "lessThan": "4.13", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.266", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.217", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.184", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.153", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.105", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.46", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.6", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.10.266" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "5.15.217" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.1.184" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.6.153" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.12.105" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "6.18.46" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "7.1.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.13", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/66eec4af1e080b695229c9a20635648a6d12fedf" }, { "url": "https://git.kernel.org/stable/c/4daf06456677177f2a6044729abac59c1b49e87b" }, { "url": "https://git.kernel.org/stable/c/d5650ddbd4d42c1a916c8fe1a4c4cb573ef810a1" }, { "url": "https://git.kernel.org/stable/c/42bc06c67d94d5f2a6b33294b0c4b07d8a47c515" }, { "url": "https://git.kernel.org/stable/c/ebdf4b4f3b1474079980a2e5cd79ad65fb54db57" }, { "url": "https://git.kernel.org/stable/c/590b07ceea138d49c9b64f65d263aa902d3b4730" }, { "url": "https://git.kernel.org/stable/c/e36663145abd7024f0281dfb22fdef65f185845b" }, { "url": "https://git.kernel.org/stable/c/9f00f9cf2be293efe899db67dc5272e3a9c62717" } ], "title": "libceph: bound pg_{temp,upmap,upmap_items} length to CEPH_PG_MAX_SIZE", "x_generator": { "engine": "bippy-1.2.0" } } } }