CVE-2026-63388
HIGH
MEDIUM
Priority: 0.01
BB Relevance:
52/100
Published: 2026-08-20
Modified: 2026-10-26
First seen: 2026-10-29
Status: active
Attack Surface
Low Complexity
No Auth
No Interaction
Conf. Impact
Integ. Impact
CVSS Vector Breakdown
AV:
Local
AC:
Low
PR:
None
UI:
None
S:
Unchanged
C:
High
I:
High
A:
High
Description
Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a heap out-of-bounds write in bufferevent_sock.c when bufferevent_socket_set_conn_address_ copies a kernel-supplied AF_UNIX peer address into bufferevent_private.conn_address. Release builds compiled with NDEBUG disable the EVUTIL_ASSERT length guard, and the evhttp accept path can pass a 110-byte sockaddr from accept() into the 28-byte field. An unauthenticated local peer able to connect to an AF_UNIX listener can overwrite the adjacent dns_request pointer and heap data, causing memory corruption with confidentiality, integrity, and availability impact. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.