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.
Update Linux/Linux to 26157c82ba756767b2bd66d28a71b1bc454447f6 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scannet/nfc: fix use-after-free llcp_sock_bind/connect affects Linux/Linux (generic), Linux/Linux (generic). Severity is unknown. 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.
AI coding agents often install or upgrade packages automatically in generic. A unknown vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
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.
Update Linux/Linux to 26157c82ba756767b2bd66d28a71b1bc454447f6 if you use the affected versions. Test the change in a non-production environment first.
Local check
hol-guard supply-chain scannet/nfc: fix use-after-free llcp_sock_bind/connect affects Linux/Linux (generic), Linux/Linux (generic). Severity is unknown. 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.
AI coding agents often install or upgrade packages automatically in generic. A unknown vulnerability in a dependency can be pulled into a project through a normal install or update without a human reviewing the change, expanding the blast radius from a single package to every agent workspace that depends on it.
| Package | Affected range | Fixed version |
|---|
| Linux/Linuxgeneric | >=a1cdd18c49d23ec38097ac2c5b0d761146fc0109 <26157c82ba756767b2bd66d28a71b1bc454447f6 || >=18013007b596771bf5f5e7feee9586fb0386ad14 <ccddad6dd28530e716448e594c9ca7c76ccd0570 || >=538a6ff11516d38a61e237d2d2dc04c30c845fbe <18ae4a192a4496e48a5490b52812645d2413307c || >=adbb1d218c5f56dbae052765da83c0f57fce2a31 <48fba458fe54cc2a980a05c13e6c19b8b2cfb610 || >=c89903c9eff219a4695e63715cf922748d743f65 <e32352070bcac22be6ed8ab635debc280bb65b8c || >=6fb003e5ae18d8cda4c8a1175d9dd8db12bec049 <6b7021ed36dabf29e56842e3408781cd3b82ef6e || >=8c9e4971e142e2899606a2490b77a1208c1f4638 <374cdde4dcc9c909a60713abdbbf96d5e3e09f91 || >=c33b1cc62ac05c1dbb1cdafe2eb66da01c76ca8d <18175fe17ae043a0b81e5d511f8817825784c299 || >=c33b1cc62ac05c1dbb1cdafe2eb66da01c76ca8d <c61760e6940dd4039a7f5e84a6afc9cdbf4d82b6 || >=4.4.267 <4.4.269 || >=4.9.267 <4.9.269 || >=4.14.231 <4.14.233 || >=4.19.187 <4.19.191 || >=5.4.112 <5.4.119 || >=5.10.30 <5.10.37 || >=5.11.14 <5.11.21 | 26157c82ba756767b2bd66d28a71b1bc454447f6, ccddad6dd28530e716448e594c9ca7c76ccd0570, 18ae4a192a4496e48a5490b52812645d2413307c, 48fba458fe54cc2a980a05c13e6c19b8b2cfb610, e32352070bcac22be6ed8ab635debc280bb65b8c, 6b7021ed36dabf29e56842e3408781cd3b82ef6e, 374cdde4dcc9c909a60713abdbbf96d5e3e09f91, 18175fe17ae043a0b81e5d511f8817825784c299, c61760e6940dd4039a7f5e84a6afc9cdbf4d82b6, 4.4.269, 4.9.269, 4.14.233, 4.19.191, 5.4.119, 5.10.37, 5.11.21 |
|---|---|---|
| Linux/Linuxgeneric | 5.12 | Not reported |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by CVE List V5 (cvelist).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard| Package | Affected range | Fixed version |
|---|
| Linux/Linuxgeneric | >=a1cdd18c49d23ec38097ac2c5b0d761146fc0109 <26157c82ba756767b2bd66d28a71b1bc454447f6 || >=18013007b596771bf5f5e7feee9586fb0386ad14 <ccddad6dd28530e716448e594c9ca7c76ccd0570 || >=538a6ff11516d38a61e237d2d2dc04c30c845fbe <18ae4a192a4496e48a5490b52812645d2413307c || >=adbb1d218c5f56dbae052765da83c0f57fce2a31 <48fba458fe54cc2a980a05c13e6c19b8b2cfb610 || >=c89903c9eff219a4695e63715cf922748d743f65 <e32352070bcac22be6ed8ab635debc280bb65b8c || >=6fb003e5ae18d8cda4c8a1175d9dd8db12bec049 <6b7021ed36dabf29e56842e3408781cd3b82ef6e || >=8c9e4971e142e2899606a2490b77a1208c1f4638 <374cdde4dcc9c909a60713abdbbf96d5e3e09f91 || >=c33b1cc62ac05c1dbb1cdafe2eb66da01c76ca8d <18175fe17ae043a0b81e5d511f8817825784c299 || >=c33b1cc62ac05c1dbb1cdafe2eb66da01c76ca8d <c61760e6940dd4039a7f5e84a6afc9cdbf4d82b6 || >=4.4.267 <4.4.269 || >=4.9.267 <4.9.269 || >=4.14.231 <4.14.233 || >=4.19.187 <4.19.191 || >=5.4.112 <5.4.119 || >=5.10.30 <5.10.37 || >=5.11.14 <5.11.21 | 26157c82ba756767b2bd66d28a71b1bc454447f6, ccddad6dd28530e716448e594c9ca7c76ccd0570, 18ae4a192a4496e48a5490b52812645d2413307c, 48fba458fe54cc2a980a05c13e6c19b8b2cfb610, e32352070bcac22be6ed8ab635debc280bb65b8c, 6b7021ed36dabf29e56842e3408781cd3b82ef6e, 374cdde4dcc9c909a60713abdbbf96d5e3e09f91, 18175fe17ae043a0b81e5d511f8817825784c299, c61760e6940dd4039a7f5e84a6afc9cdbf4d82b6, 4.4.269, 4.9.269, 4.14.233, 4.19.191, 5.4.119, 5.10.37, 5.11.21 |
|---|---|---|
| Linux/Linuxgeneric | 5.12 | Not reported |
Fixed versions are reported by the source feed; confirm compatibility before updating.
Reported by CVE List V5 (cvelist).
HOL Guard can help your team review package activity against supported protection paths.
Explore HOL Guard