{"cve":"CVE-2021-47132","nvd":{"published":"2024-03-15T21:15:07.690","modified":"2026-08-04T10:16:47.977","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: fix sk_forward_memory corruption on retransmission\n\nMPTCP sk_forward_memory handling is a bit special, as such field\nis protected by the msk socket spin_lock, instead of the plain\nsocket lock.\n\nCurrently we have a code path updating such field without handling\nthe relevant lock:\n\n__mptcp_retrans() -> __mptcp_clean_una_wakeup()\n\nSeveral helpers in __mptcp_clean_una_wakeup() will update\nsk_forward_alloc, possibly causing such field corruption, as reported\nby Matthieu.\n\nAddress the issue providing and using a new variant of blamed function\nwhich explicitly acquires the msk spin lock.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1},"cwes":["CWE-787"],"references":["https://git.kernel.org/stable/c/b5941f066b4ca331db225a976dae1d6ca8cf0ae3","https://git.kernel.org/stable/c/b9c78b1a95966a7bd2ddae05b73eafc0cda4fba3","https://git.kernel.org/stable/c/b5941f066b4ca331db225a976dae1d6ca8cf0ae3","https://git.kernel.org/stable/c/b9c78b1a95966a7bd2ddae05b73eafc0cda4fba3"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:46:54.846886191+00:00"},"epss":{"cve":"CVE-2021-47132","score":0.00483,"percentile":0.41636,"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."]}