{"cve":"CVE-2023-54039","nvd":{"published":"2025-12-24T11:15:56.890","modified":"2026-06-17T06:46:41.667","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: j1939: j1939_tp_tx_dat_new(): fix out-of-bounds memory access\n\nIn the j1939_tp_tx_dat_new() function, an out-of-bounds memory access\ncould occur during the memcpy() operation if the size of skb->cb is\nlarger than the size of struct j1939_sk_buff_cb. This is because the\nmemcpy() operation uses the size of skb->cb, leading to a read beyond\nthe struct j1939_sk_buff_cb.\n\nUpdated the memcpy() operation to use the size of struct\nj1939_sk_buff_cb instead of the size of skb->cb. This ensures that the\nmemcpy() operation only reads the memory within the bounds of struct\nj1939_sk_buff_cb, preventing out-of-bounds memory access.\n\nAdditionally, add a BUILD_BUG_ON() to check that the size of skb->cb\nis greater than or equal to the size of struct j1939_sk_buff_cb. This\nensures that the skb->cb buffer is large enough to hold the\nj1939_sk_buff_cb structure.\n\n[mkl: rephrase commit message]","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/36befc9aed6202b4a9b906529aea13eacd7e34ff","https://git.kernel.org/stable/c/4c3fb22a6ec68258ee129a2e6b720f43dffc562f","https://git.kernel.org/stable/c/4fe1d9b6231a68ffc91318f57fd8e4982f028cf7","https://git.kernel.org/stable/c/70caa596d158a5d84b117f722d58f3ea503a5ba9","https://git.kernel.org/stable/c/b45193cb4df556fe6251b285a5ce44046dd36b4a"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:17:07.138532058+00:00"},"epss":{"cve":"CVE-2023-54039","score":0.00192,"percentile":0.0887,"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."]}