CVE-2021-47297

MEDIUM
Published May 21, 2024 Modified Apr 2, 2025 CWE-908

Description

In the Linux kernel, the following vulnerability has been resolved: net: fix uninit-value in caif_seqpkt_sendmsg When nr_segs equal to zero in iovec_from_user, the object msg->msg_iter.iov is uninit stack memory in caif_seqpkt_sendmsg which is defined in ___sys_sendmsg. So we cann't just judge msg->msg_iter.iov->base directlly. We can use nr_segs to judge msg in caif_seqpkt_sendmsg whether has data buffers. ===================================================== BUG: KMSAN: uninit-value in caif_seqpkt_sendmsg+0x693/0xf60 net/caif/caif_socket.c:542 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 caif_seqpkt_sendmsg+0x693/0xf60 net/caif/caif_socket.c:542 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2343 ___sys_sendmsg net/socket.c:2397 [inline] __sys_sendmmsg+0x808/0xc90 net/socket.c:2480 __compat_sys_sendmmsg net/compat.c:656 [inline]

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CVSS v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-908 CWE-908

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/1582a02fecffcee306663035a295e28e1c4aaaff https://git.kernel.org/stable/c/452c3ed7bf63721b07bc2238ed1261bb26027e85 https://git.kernel.org/stable/c/5c6d8e2f7187b8e45a18c27acb7a3885f03ee3db https://git.kernel.org/stable/c/9413c0abb57f70a953b1116318d6aa478013c35d https://git.kernel.org/stable/c/991e634360f2622a683b48dfe44fe6d9cb765a09 https://git.kernel.org/stable/c/d4c7797ab1517515f0d08b3bc1c6b48883889c54 https://git.kernel.org/stable/c/d9d646acad2c3590e189bb5d5c86ab8bd8a2dfc3 https://git.kernel.org/stable/c/ffe31dd70b70a40cd6b21b78c1713a23e021843a https://git.kernel.org/stable/c/1582a02fecffcee306663035a295e28e1c4aaaff https://git.kernel.org/stable/c/452c3ed7bf63721b07bc2238ed1261bb26027e85 https://git.kernel.org/stable/c/5c6d8e2f7187b8e45a18c27acb7a3885f03ee3db https://git.kernel.org/stable/c/9413c0abb57f70a953b1116318d6aa478013c35d https://git.kernel.org/stable/c/991e634360f2622a683b48dfe44fe6d9cb765a09 https://git.kernel.org/stable/c/d4c7797ab1517515f0d08b3bc1c6b48883889c54 https://git.kernel.org/stable/c/d9d646acad2c3590e189bb5d5c86ab8bd8a2dfc3 https://git.kernel.org/stable/c/ffe31dd70b70a40cd6b21b78c1713a23e021843a

Frequently Asked Questions

What is CVE-2021-47297? +
In the Linux kernel, the following vulnerability has been resolved: net: fix uninit-value in caif_seqpkt_sendmsg When nr_segs equal to zero in iovec_from_user, the object msg->msg_iter.iov is uninit stack memory in caif_seqpkt_sendmsg which is defined in ___sys_sendmsg. So we cann't just judge msg->msg_iter.iov->base directlly. We can use nr_segs to judge msg in caif_seqpkt_sendmsg whether has data buffers. ===================================================== BUG: KMSAN: uninit-value in caif_seqpkt_sendmsg+0x693/0xf60 net/caif/caif_socket.c:542 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 caif_seqpkt_sendmsg+0x693/0xf60 net/caif/caif_socket.c:542 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2343 ___sys_sendmsg net/socket.c:2397 [inline] __sys_sendmmsg+0x808/0xc90 net/socket.c:2480 __compat_sys_sendmmsg net/compat.c:656 [inline] It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2021-47297? +
CVE-2021-47297 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2021-47297? +
CVE-2021-47297 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2021-47297? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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