cbcvebase.
CVE-2025-39946
published 2025-10-04

CVE-2025-39946: In the Linux kernel, the following vulnerability has been resolved: tls: make sure to abort the stream if headers are bogus Normally we wait for the socket to…

PriorityP334medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
8.94%
94.7th percentile
In the Linux kernel, the following vulnerability has been resolved: tls: make sure to abort the stream if headers are bogus Normally we wait for the socket to buffer up the whole record before we service it. If the socket has a tiny buffer, however, we read out the data sooner, to prevent connection stalls. Make sure that we abort the connection when we find out late that the record is actually invalid. Retrying the parsing is fine in itself but since we copy some more data each time before we parse we can overflow the allocated skb space. Constructing a scenario in which we're under pressure without enough data in the socket to parse the length upfront is quite hard. syzbot figured out a way to do this by serving us the header in small OOB sends, and then filling in the recvbuf with a large normal send. Make sure that tls_rx_msg_size() aborts strp, if we reach an invalid record there's really no way to recover.

Affected

28 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
debianlinux-6.1< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
linuxlinux
linuxlinux>= 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < b36462146d86b1f22e594fe4dae611dffacfb203b36462146d86b1f22e594fe4dae611dffacfb203
linuxlinux>= 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 4cefe5be73886f383639fe0850bb72d5b568a7b94cefe5be73886f383639fe0850bb72d5b568a7b9
linuxlinux>= 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 208640e6225cc929a05adbf79d1df558add3e231208640e6225cc929a05adbf79d1df558add3e231
linuxlinux>= 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 61ca2da5fb8f433ce8bbd1657c84a86272133e6b61ca2da5fb8f433ce8bbd1657c84a86272133e6b
linuxlinux>= 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 0aeb54ac4cd5cf8f60131b4d9ec0b6dc9c27b20d0aeb54ac4cd5cf8f60131b4d9ec0b6dc9c27b20d
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.158-16.1.158-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.16.9-16.16.9-1
linuxlinux_kernel>= 0 < 6.8.0-100.1006.8.0-100.100
linuxlinux_kernel>= 6.0 < 6.1.1546.1.154
linuxlinux_kernel>= 6.13 < 6.16.96.16.9
linuxlinux_kernel>= 6.2 < 6.6.1086.6.108
linuxlinux_kernel>= 6.7 < 6.12.496.12.49
msrcazl3_kernel_6.6.104.2-4_on_azure_linux_3.0
msrcazl3_kernel_6.6.96.2-2_on_azure_linux_3.0
ubuntulinux-aws
ubuntulinux-aws-6.8
ubuntulinux-gkeop
ubuntulinux-nvidia
ubuntulinux-nvidia-6.8
ubuntulinux-oracle

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
vendor_ubuntu9.8CRITICAL
vendor_msrc5.5MEDIUM
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