{"cve":"CVE-2021-47542","nvd":{"published":"2024-05-24T15:15:18.550","modified":"2026-06-17T04:17:43.670","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: qlogic: qlcnic: Fix a NULL pointer dereference in qlcnic_83xx_add_rings()\n\nIn qlcnic_83xx_add_rings(), the indirect function of\nahw->hw_ops->alloc_mbx_args will be called to allocate memory for\ncmd.req.arg, and there is a dereference of it in qlcnic_83xx_add_rings(),\nwhich could lead to a NULL pointer dereference on failure of the\nindirect function like qlcnic_83xx_alloc_mbx_args().\n\nFix this bug by adding a check of alloc_mbx_args(), this patch\nimitates the logic of mbx_cmd()'s failure handling.\n\nThis bug was found by a static analyzer. The analysis employs\ndifferential checking to identify inconsistent security operations\n(e.g., checks or kfrees) between two code paths and confirms that the\ninconsistent operations are not recovered in the current function or\nthe callers, so they constitute bugs.\n\nNote that, as a bug found by static analysis, it can be a false\npositive or hard to trigger. Multiple researchers have cross-reviewed\nthe bug.\n\nBuilds with CONFIG_QLCNIC=m show no new warnings, and our\nstatic analyzer no longer warns about this code.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/15fa12c119f869173f9b710cbe6a4a14071d2105","https://git.kernel.org/stable/c/3a061d54e260b701b538873b43e399d9b8b83e03","https://git.kernel.org/stable/c/550658a2d61e4eaf522c8ebc7fad76dc376bfb45","https://git.kernel.org/stable/c/57af54a56024435d83e44c78449513b414eb6edf","https://git.kernel.org/stable/c/b4f217d6fcc00c3fdc0921a7691f30be7490b073"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47542","score":0.00251,"percentile":0.16504,"date":"2026-10-31"},"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."]}