In the Linux kernel, the following vulnerability has been resolved:
tcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO)
do_tcp_getsockopt() reads icsk->icsk_ca_ops and dereferences the
get_info function pointer without rcu_read_lock(). With BPF struct_ops
congestion control, ca_ops can point to dynamically allocated memory
that is freed concurrently, resulting in a use-after-free when the
kernel dereferences or calls through the stale pointer.
BUG: KASAN: slab-use-after-free in do_tcp_getsockopt+0x2037/0x23e0
Read of size 8 at addr ffff888013701258 by task exploit/149
do_tcp_getsockopt+0x2037/0x23e0 (net/ipv4/tcp.c:4564)
tcp_getsockopt+0x91/0xf0
__sys_getsockopt+0xf7/0x170
Fix this by wrapping the ca_ops load and get_info call within
rcu_read_lock()/rcu_read_unlock(), and using READ_ONCE() to load
the icsk_ca_ops pointer.
Metrics
Affected Vendors & Products
| Vendors | Products |
|---|---|
| Linux |
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No data.
No data.
References
History
Wed, 28 Oct 2026 13:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux linux
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| Vendors & Products |
Linux linux
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Wed, 28 Oct 2026 12:30:00 +0000
| Type | Values Removed | Values Added |
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| Weaknesses | CWE-416 |
Wed, 28 Oct 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
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| Description | In the Linux kernel, the following vulnerability has been resolved: tcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO) do_tcp_getsockopt() reads icsk->icsk_ca_ops and dereferences the get_info function pointer without rcu_read_lock(). With BPF struct_ops congestion control, ca_ops can point to dynamically allocated memory that is freed concurrently, resulting in a use-after-free when the kernel dereferences or calls through the stale pointer. BUG: KASAN: slab-use-after-free in do_tcp_getsockopt+0x2037/0x23e0 Read of size 8 at addr ffff888013701258 by task exploit/149 do_tcp_getsockopt+0x2037/0x23e0 (net/ipv4/tcp.c:4564) tcp_getsockopt+0x91/0xf0 __sys_getsockopt+0xf7/0x170 Fix this by wrapping the ca_ops load and get_info call within rcu_read_lock()/rcu_read_unlock(), and using READ_ONCE() to load the icsk_ca_ops pointer. | |
| Title | tcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO) | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
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MITRE
Status: PUBLISHED
Assigner: Linux
Published: 2026-10-28T10:34:49.993Z
Updated: 2026-10-28T10:34:49.993Z
Reserved: 2026-09-25T10:25:14.395Z
Link: CVE-2026-99138
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-28T11:17:33.740
Modified: 2026-10-28T11:17:33.740
Link: CVE-2026-99138
Redhat
No data.