๐Ÿ” CVE Alert

CVE-2025-39946

CRITICAL 9.8

tls: make sure to abort the stream if headers are bogus

CVSS Score
9.8
EPSS Score
0.0%
EPSS Percentile
1th

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.

Vendor linux
Product linux
Ecosystems
Industries
Technology
Published Oct 4, 2025
Last Updated Apr 2, 2026
Stay Ahead of the Next One

Get instant alerts for linux linux

Be the first to know when new critical vulnerabilities affecting linux linux are published โ€” delivered to Slack, Telegram or Discord.

Get Free Alerts โ†’ Free ยท No credit card ยท 60 sec setup

CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability

Affected Versions

Linux / Linux
84c61fe1a75b4255df1e1e7c054c9e6d048da417 < b36462146d86b1f22e594fe4dae611dffacfb203 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 4cefe5be73886f383639fe0850bb72d5b568a7b9 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 208640e6225cc929a05adbf79d1df558add3e231 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 61ca2da5fb8f433ce8bbd1657c84a86272133e6b 84c61fe1a75b4255df1e1e7c054c9e6d048da417 < 0aeb54ac4cd5cf8f60131b4d9ec0b6dc9c27b20d
Linux / Linux
6.0

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
git.kernel.org: https://git.kernel.org/stable/c/b36462146d86b1f22e594fe4dae611dffacfb203 git.kernel.org: https://git.kernel.org/stable/c/4cefe5be73886f383639fe0850bb72d5b568a7b9 git.kernel.org: https://git.kernel.org/stable/c/208640e6225cc929a05adbf79d1df558add3e231 git.kernel.org: https://git.kernel.org/stable/c/61ca2da5fb8f433ce8bbd1657c84a86272133e6b git.kernel.org: https://git.kernel.org/stable/c/0aeb54ac4cd5cf8f60131b4d9ec0b6dc9c27b20d