{"id":"CVE-2026-120689","aliases":["AZL-112526","DEBIAN-CVE-2026-120689","EUVD-2026-115545","GHSA-6384-wh38-r9pf","UBUNTU-CVE-2026-120689"],"status":"published","title":"Uncontrolled Recursion in HDF5 H5B__iterate_helper() via Crafted File","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","severity":{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00176,"percentile":0.07213,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-674"],"published":"2026-11-02T19:39:28Z","modified":"2026-11-04T03:30:39Z","affected":[{"source":"osv","ecosystem":"Azure Linux:3","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.14.6-6"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.10.10+repack-1","1.10.10+repack-2","1.10.10+repack-3","1.10.10+repack-3.1","1.10.10+repack-3.2","1.10.10+repack-3.2+ports","1.10.10+repack-3.3","1.10.10+repack-4","1.10.10+repack-5","1.10.8+repack1-1","1.12.0+repack-1~exp1","1.12.0+repack-1~exp2","1.12.2+repack-1~exp1","1.14.3+repack-1~exp1","1.14.3+repack1-1~exp2","1.14.3+repack1-1~exp3","1.14.4.3+repack-1~exp1","1.14.4.3+repack-1~exp2","1.14.4.3+repack-1~exp3","1.14.5+repack-1","1.14.5+repack-1~exp1","1.14.5+repack-1~exp2","1.14.5+repack-1~exp3","1.14.5+repack-1~exp4","1.14.5+repack-1~exp5","1.14.5+repack-1~exp6","1.14.5+repack-2","1.14.5+repack-3","1.14.5+repack-3.1","1.14.5+repack-3~exp1","1.14.5+repack-3~exp2","1.14.5+repack-3~exp3","1.14.5+repack-3~exp4","1.14.5+repack-4","1.14.5+repack-4~exp1","1.14.5+repack-4~exp2","1.14.5+repack-5~exp2","1.14.5+repack-5~exp3","1.14.6+repack-1","1.14.6+repack-1~exp1","1.14.6+repack-1~exp10","1.14.6+repack-1~exp11","1.14.6+repack-1~exp12","1.14.6+repack-1~exp13","1.14.6+repack-1~exp14","1.14.6+repack-1~exp15","1.14.6+repack-1~exp16","1.14.6+repack-1~exp17","1.14.6+repack-1~exp18","1.14.6+repack-1~exp19","1.14.6+repack-1~exp2","1.14.6+repack-1~exp20","1.14.6+repack-1~exp21","1.14.6+repack-1~exp3","1.14.6+repack-1~exp4","1.14.6+repack-1~exp5","1.14.6+repack-1~exp6","1.14.6+repack-1~exp7","1.14.6+repack-1~exp8","1.14.6+repack-1~exp9","1.14.6+repack-2","1.14.6+repack-3~exp1","2.1.0+repack-1","2.1.0+repack-1~exp10","2.1.0+repack-1~exp11","2.1.0+repack-1~exp3","2.1.0+repack-1~exp4","2.1.0+repack-1~exp5","2.1.0+repack-1~exp6","2.1.0+repack-1~exp7","2.1.0+repack-1~exp8","2.1.0+repack-1~exp9","2.2.0+repack-1","2.2.0+repack-2","2.2.0+repack-3","2.2.0+repack-4","2.2.0+repack-5","2.2.0+repack-6"]},{"source":"osv","ecosystem":"Debian:13","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.14.5+repack-3","1.14.5+repack-3.1","1.14.5+repack-4","1.14.5+repack-4~exp1","1.14.5+repack-4~exp2","1.14.5+repack-5~exp2","1.14.5+repack-5~exp3","1.14.6+repack-1","1.14.6+repack-1~exp1","1.14.6+repack-1~exp10","1.14.6+repack-1~exp11","1.14.6+repack-1~exp12","1.14.6+repack-1~exp13","1.14.6+repack-1~exp14","1.14.6+repack-1~exp15","1.14.6+repack-1~exp16","1.14.6+repack-1~exp17","1.14.6+repack-1~exp18","1.14.6+repack-1~exp19","1.14.6+repack-1~exp2","1.14.6+repack-1~exp20","1.14.6+repack-1~exp21","1.14.6+repack-1~exp3","1.14.6+repack-1~exp4","1.14.6+repack-1~exp5","1.14.6+repack-1~exp6","1.14.6+repack-1~exp7","1.14.6+repack-1~exp8","1.14.6+repack-1~exp9","1.14.6+repack-2","1.14.6+repack-3~exp1","2.1.0+repack-1","2.1.0+repack-1~exp10","2.1.0+repack-1~exp11","2.1.0+repack-1~exp3","2.1.0+repack-1~exp4","2.1.0+repack-1~exp5","2.1.0+repack-1~exp6","2.1.0+repack-1~exp7","2.1.0+repack-1~exp8","2.1.0+repack-1~exp9","2.2.0+repack-1","2.2.0+repack-2","2.2.0+repack-3","2.2.0+repack-4","2.2.0+repack-5","2.2.0+repack-6"]},{"source":"osv","ecosystem":"Debian:14","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.14.5+repack-3","1.14.5+repack-3.1","1.14.5+repack-4","1.14.5+repack-4~exp1","1.14.5+repack-4~exp2","1.14.5+repack-5~exp2","1.14.5+repack-5~exp3","1.14.6+repack-1","1.14.6+repack-1~exp1","1.14.6+repack-1~exp10","1.14.6+repack-1~exp11","1.14.6+repack-1~exp12","1.14.6+repack-1~exp13","1.14.6+repack-1~exp14","1.14.6+repack-1~exp15","1.14.6+repack-1~exp16","1.14.6+repack-1~exp17","1.14.6+repack-1~exp18","1.14.6+repack-1~exp19","1.14.6+repack-1~exp2","1.14.6+repack-1~exp20","1.14.6+repack-1~exp21","1.14.6+repack-1~exp3","1.14.6+repack-1~exp4","1.14.6+repack-1~exp5","1.14.6+repack-1~exp6","1.14.6+repack-1~exp7","1.14.6+repack-1~exp8","1.14.6+repack-1~exp9","1.14.6+repack-2","1.14.6+repack-3~exp1","2.1.0+repack-1","2.1.0+repack-1~exp10","2.1.0+repack-1~exp11","2.1.0+repack-1~exp3","2.1.0+repack-1~exp4","2.1.0+repack-1~exp5","2.1.0+repack-1~exp6","2.1.0+repack-1~exp7","2.1.0+repack-1~exp8","2.1.0+repack-1~exp9","2.2.0+repack-1","2.2.0+repack-2","2.2.0+repack-3","2.2.0+repack-4","2.2.0+repack-5","2.2.0+repack-6"]},{"source":"osv","ecosystem":"Ubuntu:Pro:14.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.11-3ubuntu1","1.8.11-5ubuntu1","1.8.11-5ubuntu2","1.8.11-5ubuntu6","1.8.11-5ubuntu7","1.8.11-5ubuntu7.1","1.8.11-5ubuntu7.1+esm1","1.8.11-5ubuntu7.1+esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.15-patch1+docs-4","1.8.15-patch1+docs-5","1.8.16+docs-1","1.8.16+docs-2","1.8.16+docs-3","1.8.16+docs-3ubuntu1","1.8.16+docs-4","1.8.16+docs-4ubuntu1","1.8.16+docs-4ubuntu1.1","1.8.16+docs-4ubuntu1.1+esm1","1.8.16+docs-4ubuntu1.1+esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.10.0-patch1+docs-4","1.10.0-patch1+docs-4ubuntu0.1~esm1","1.10.0-patch1+docs-4ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.10.4+repack-10","1.10.4+repack-11","1.10.4+repack-11ubuntu1","1.10.4+repack-11ubuntu1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.10.6+repack-5","1.10.7+repack-4ubuntu1","1.10.7+repack-4ubuntu2"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.10.8+repack1-1ubuntu1","1.10.10+repack-3ubuntu1","1.10.10+repack-3.1ubuntu3","1.10.10+repack-3.1ubuntu4"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.14.6+repack-2","2.2.0+repack-4","2.2.0+repack-5"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"hdf5","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.14.5+repack-3build1","1.14.5+repack-4","1.14.6+repack-2"]}],"products":[{"vendor":"hdfgroup","product":"hdf5"},{"vendor":"the hdf group","product":"hdf5"}],"references":[{"url":"https://github.com/HDFGroup/hdf5/issues/6403","tags":["report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-120689","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-6384-wh38-r9pf"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/120xxx/CVE-2026-120689.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-120689","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-120689","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-120689","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-120689","title":"Uncontrolled Recursion in HDF5 H5B__iterate_helper() via Crafted File","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T19:39:28.327Z","modified":"2026-11-02T19:52:35.578Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium","assessor":"cna"}],"cwes":["CWE-674"],"updated_at":"2026-11-02T20:51:25.833244Z"}],"euvd":[{"id":"EUVD-2026-115545","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T19:39:28Z","modified":"2026-11-02T19:52:35Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"updated_at":"2026-11-03T05:08:37.762119Z"}],"ghsa":[{"id":"GHSA-6384-wh38-r9pf","title":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in...","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T21:31:59Z","modified":"2026-11-02T21:32:06Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"cwes":["CWE-674"],"updated_at":"2026-11-03T00:02:48.181039Z"}],"nvd":[{"id":"CVE-2026-120689","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T20:17:41.02Z","modified":"2026-11-03T16:25:21.31Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-674"],"updated_at":"2026-11-03T18:16:47.713454Z"}],"osv":[{"id":"CVE-2026-120689","title":"Uncontrolled Recursion in HDF5 H5B__iterate_helper() via Crafted File","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T19:39:28.327Z","modified":"2026-11-05T02:30:25.620026101Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"updated_at":"2026-11-07T03:08:01.726202Z"},{"id":"DEBIAN-CVE-2026-120689","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T20:17:41.02Z","modified":"2026-11-04T09:47:37.040655744Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"updated_at":"2026-11-04T10:05:32.187009Z"},{"id":"UBUNTU-CVE-2026-120689","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T20:17:00Z","modified":"2026-11-05T04:42:52Z","cvss":[{"version":"4.0","score":4.3,"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U","level":"medium"}],"updated_at":"2026-11-05T13:33:25.727744Z"},{"id":"AZL-112526","title":"CVE-2026-120689 affecting package hdf5 1.14.6-6","description":"HDF5 through 2.2.0 contains an uncontrolled recursion vulnerability in H5B__iterate_helper() in src/H5B.c. When iterating a version 1 B-tree, the function does not verify that a child node’s level matches the expected level. That check is performed only in H5B__cache_deserialize() when a node is first loaded into the metadata cache. A crafted HDF5 file whose B-tree child pointer refers back to a node already in the cache, such as a node that points to itself, bypasses the check and causes unbounded recursion, leading to stack exhaustion and a crash. This can be triggered by calling H5Gget_info() or H5Gget_num_objs() on a group in the crafted file, which reaches H5B_iterate() through H5G__obj_info() and H5G__stab_count(). An attacker who can get a user or application to open a malicious file can cause a denial of service.","status":"published","published":"2026-11-02T20:17:41Z","modified":"2026-11-05T05:40:51Z","updated_at":"2026-11-05T16:41:19.001909Z"}]}}