{"id":"CVE-2026-39956","summary":"jq: Missing runtime type checks for _strindices lead to crash and limited memory disclosure","details":"jq is a command-line JSON processor. In commits after 69785bf77f86e2ea1b4a20ca86775916889e91c9, the _strindices builtin in jq's src/builtin.c passes its arguments directly to jv_string_indexes() without verifying they are strings, and jv_string_indexes() in src/jv.c relies solely on assert() checks that are stripped in release builds compiled with -DNDEBUG. This allows an attacker to crash jq trivially with input like _strindices(0), and by crafting a numeric value whose IEEE-754 bit pattern maps to a chosen pointer, achieve a controlled pointer dereference and limited memory read/probe primitive. Any deployment that evaluates untrusted jq filters against a release build is vulnerable. This issue has been patched in commit fdf8ef0f0810e3d365cdd5160de43db46f57ed03.","aliases":["GHSA-6gc3-3g9p-xx28"],"modified":"2026-07-15T18:29:43.200966439Z","published":"2026-04-13T22:10:18.817Z","related":["SUSE-SU-2026:22545-1","SUSE-SU-2026:22566-1","SUSE-SU-2026:2983-1","openSUSE-SU-2026:10850-1","openSUSE-SU-2026:21248-1"],"database_specific":{"unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"69785bf77f86e2ea1b4a20ca86775916889e91c9"},{"fixed":"fdf8ef0f0810e3d365cdd5160de43db46f57ed03"}]}],"cna_assigner":"GitHub_M","cwe_ids":["CWE-125","CWE-476","CWE-843"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39956.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39956.json"},{"type":"ADVISORY","url":"https://github.com/jqlang/jq/security/advisories/GHSA-6gc3-3g9p-xx28"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39956"},{"type":"FIX","url":"https://github.com/jqlang/jq/commit/fdf8ef0f0810e3d365cdd5160de43db46f57ed03"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/jqlang/jq","events":[{"introduced":"0"},{"fixed":"fdf8ef0f0810e3d365cdd5160de43db46f57ed03"}],"database_specific":{"source":"REFERENCES"}}],"versions":["jq-1.8.1","jq-1.8.0","jq-1.7.1","jq-1.7","jq-1.7rc2","jq-1.7rc1","jq-1.6","1.6rc2","jq-1.6rc1","jq-1.5rc2","jq-1.5rc1","jq-1.4","jq-1.3","jq-1.2","jq-1.1","jq-1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-39956.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H"}]}