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.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade linux | Jul 30, 2024 | Feb 29, 2024 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Feb 29, 2024 |
| Suse | — | Upgrade kernel-obs-buildUpgrade kernel-azureUpgrade kernel-develUpgrade reiserfs-kmp-defaultUpgrade kernel-docsUpgrade kernel-preempt-develUpgrade kernel-default-baseUpgrade kernel-defaultUpgrade kernel-macrosUpgrade kernel-azure-develUpgrade kernel-default-extraUpgrade kernel-preemptUpgrade kernel-default-develUpgrade kernel-syms-azureUpgrade kernel-sourceUpgrade kernel-64kb-develUpgrade kernel-default-manUpgrade kernel-64kbUpgrade kernel-symsUpgrade kernel-devel-azureUpgrade kernel-source-azureUpgrade kernel-zfcpdumpUpgrade kernel-azure-base | Aug 9, 2024 | Feb 29, 2024 |
| Ubuntu | — | Upgrade linux-azure-5.4Upgrade linux-kvmUpgrade linux-aws-hweUpgrade linux-gcp-fipsUpgrade linux-bluefieldUpgrade linux-gcp-4.15Upgrade linux-oracleUpgrade linux-azureUpgrade linux-hwe-5.4Upgrade linux-gkeopUpgrade linux-gcpUpgrade linux-aws-5.4Upgrade linux-fipsUpgrade linux-raspiUpgrade linux-raspi-5.4Upgrade linux-hweUpgrade linux-aws-fipsUpgrade linux-azure-fipsUpgrade linux-azure-4.15Upgrade linuxUpgrade linux-awsUpgrade linux-gcp-5.4Upgrade linux-oracle-5.4 | Nov 19, 2024 | Feb 29, 2024 |
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