{"cve":"CVE-2026-97923","nvd":{"published":"2026-09-25T11:17:19.413","modified":"2026-10-19T10:17:43.060","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntracing: Free histogram the var ref when its initialization fails\n\ncreate_var_ref() allocates a VAR_REF hist_field and then calls\ninit_var_ref() to fill it in. When that fails the field is leaked.\n\ncommit 656fe2ba85e8 (\"tracing: Use hist trigger's var_ref array to destroy\nvar_refs\") made destroy_hist_field() return early for\nHIST_FIELD_FL_VAR_REF, since var refs are freed by walking the trigger's\nvar_refs[] array instead. create_var_ref() adds the field to that array\nonly after init_var_ref() has succeeded, so on this path the field is in\nneither place and nothing frees it. The call was correct when it was\nwritten, before var refs were taken out of destroy_hist_field().\n\ninit_var_ref() cannot free it either. The caller owns the field, so\ninit_var_ref() undoes only its own string allocations and leaves the\nfield alone. Freeing it there would leave create_var_ref() passing freed\nmemory to destroy_hist_field(), which reads its flags.\n\nCall __destroy_hist_field(), which frees the field without consulting\nthe flag.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/222abcbe7866fef04563b6eb89fb21f627dcbc77","https://git.kernel.org/stable/c/352f84a381e7b4651b30366e93cb858f3fa9c91a","https://git.kernel.org/stable/c/4870f9071c9ea3c1423a07741b85a794db30d672","https://git.kernel.org/stable/c/4924328d6991f25b65bb7c8ff5d56c2a9b254851","https://git.kernel.org/stable/c/516001d53e6b2ea95a251ee2ef54a1a689a3fd58"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:02.509636177+00:00"},"epss":{"cve":"CVE-2026-97923","score":0.00211,"percentile":0.11181,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}