{"id":"CVE-2026-68159","title":"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 over…","summary":"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 over…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","published":"2026-08-10","updated":"2026-08-23","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-68159","references":[{"url":"https://git.kernel.org/stable/c/42bc06c67d94d5f2a6b33294b0c4b07d8a47c515","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4daf06456677177f2a6044729abac59c1b49e87b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/590b07ceea138d49c9b64f65d263aa902d3b4730","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/66eec4af1e080b695229c9a20635648a6d12fedf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9f00f9cf2be293efe899db67dc5272e3a9c62717","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d5650ddbd4d42c1a916c8fe1a4c4cb573ef810a1","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/e36663145abd7024f0281dfb22fdef65f185845b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ebdf4b4f3b1474079980a2e5cd79ad65fb54db57","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-68159.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-68159"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2513165"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68159"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68159"},{"url":"https://access.redhat.com/errata/RHSA-2026:68570"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.00745,"epssPercentile":0.52867,"ingestedAt":"2026-08-23T13:48:06.405Z","vendor":"Red Hat","product":"Red Hat Enterprise Linux BaseOS (v. 9)","affected":["enterprise_linux 10","enterprise_linux 7","enterprise_linux 8","enterprise_linux 9","enterprise_linux_for_nvidia 26","openshift_container_platform 4","enterprise_linux_appstream_v_9","enterprise_linux_baseos_v_9","enterprise_linux_codeready_linux_builder_v_9","enterprise_linux_real_time_for_nfv_v_9","enterprise_linux_real_time_v_9"],"patched":["enterprise_linux_appstream_v_9","enterprise_linux_baseos_v_9","enterprise_linux_codeready_linux_builder_v_9","enterprise_linux_real_time_for_nfv_v_9","enterprise_linux_real_time_v_9"],"cwe":["CWE-787"],"scores":{"nvd":9.8,"vendor":8.8},"slug":"CVE-2026-68159","body":"## Overview\n\nIn 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() ]\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:68570** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9), Red Hat Enterprise Linux Real Time for NFV (v. 9), Red Hat Enterprise Linux Real Time (v. 9) · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68570)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux for NVIDIA 26, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 9, … · updated 2026-09-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-68159.json)","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}