CVE-2021-47068
highpriority · track · 31EPSS 0.002 · 14 %ileDEEURUUSEPSS · scored 2026-10-27
In the Linux kernel, the following vulnerability has been resolved: net/nfc: fix use-after-free llcp_sock_bind/connect Commits 8a4cd82d ("nfc: fix refcount leak in llcp_sock_connect()") and c33b1cc62 ("nfc: fix refcount leak in llcp_sock_bind()") fixed a refcount leak bug in bind/connect but introduced a use-after-free if the same local is assigned to 2 different sockets. This can be triggered by the following simple program: int sock1 = socket( AF_NFC, SOCK_STREAM, NFC_SOCKPROTO_LLCP ); int sock2 = socket( AF_NFC, SOCK_STREAM, NFC_SOCKPROTO_LLCP ); memset( &addr, 0, sizeof(struct sockaddr_nfc_llcp) ); addr.sa_family = AF_NFC; addr.nfc_protocol = NFC_PROTO_NFC_DEP; bind( sock1, (struct sockaddr*) &addr, sizeof(struct sockaddr_nfc_llcp) ) bind( sock2, (struct sockaddr*) &addr, sizeof(struct sockaddr_nfc_llcp) ) close(sock1); close(sock2); Fix this by assigning NULL to llcp_sock->local after calling nfc_llcp_local_put. This addresses CVE-2021-23134.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (81)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2024-0527Linux Kernel: Mehrere SchwachstellenDeutsch2024-02-29csaf · cert_bundDE
Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Zustand zu verursachen und einen nicht näher spezifizierten Angriff durchzuführen.
also known as (4)
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sources
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references (30)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2021-47068/cnnvd
- https://git.kernel.org/stable/c/18175fe17ae043a0b81e5d511f8817825784c299cnnvd
- https://git.kernel.org/stable/c/18ae4a192a4496e48a5490b52812645d2413307ccnnvd
- https://git.kernel.org/stable/c/26157c82ba756767b2bd66d28a71b1bc454447f6cnnvd
- https://git.kernel.org/stable/c/374cdde4dcc9c909a60713abdbbf96d5e3e09f91cnnvd
- https://git.kernel.org/stable/c/48fba458fe54cc2a980a05c13e6c19b8b2cfb610cnnvd
- https://git.kernel.org/stable/c/6b7021ed36dabf29e56842e3408781cd3b82ef6ecnnvd
- https://git.kernel.org/stable/c/c61760e6940dd4039a7f5e84a6afc9cdbf4d82b6cnnvd
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