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CVE-2026-63388

CVE-2026-63388 · Libevent: Heap out-of-bounds write in bufferevent_socket_set_conn_address_ reachable via AF_UNIX accept

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 8.4 · High · EPSS 0.1% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • libevent

    Versions
    • < 2.1.13: Affected
    • >= 2.2.0-alpha, < 2.2.2-alpha: Affected

    No fix published

  • libevent Debian:12

    Versions
    • 2.1.12-stable-8
    Affected ranges
    • ECOSYSTEM: < 2.1.12-stable-8+deb12u1

    Update to 2.1.12-stable-8+deb12u1

  • libevent Debian:13

    Versions
    • 2.1.12-stable-10
    Affected ranges
    • ECOSYSTEM: < 2.1.13-stable-1~deb13u1

    Update to 2.1.13-stable-1~deb13u1

  • libevent Debian:14

    Versions
    • 2.1.12-stable-10
    • 2.1.13-stable-1~deb13u1
    Affected ranges
    • ECOSYSTEM: < 2.1.13-stable-1

    Update to 2.1.13-stable-1

  • libevent Ubuntu:Pro:18.04:LTS

    Versions
    • 2.1.8-stable-4
    • 2.1.8-stable-4build1
    • 2.1.8-stable-4ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: < 2.1.8-stable-4ubuntu0.1~esm2

    Update to 2.1.8-stable-4ubuntu0.1~esm2

  • libevent Ubuntu:Pro:20.04:LTS

    Versions
    • 2.1.8-stable-4build1
    • 2.1.11-stable-1~exp0
    • 2.1.11-stable-1
    • 2.1.11-stable-1ubuntu0.1~esm1
    Affected ranges
    • ECOSYSTEM: < 2.1.11-stable-1ubuntu0.1~esm2

    Update to 2.1.11-stable-1ubuntu0.1~esm2

  • libevent Ubuntu:22.04:LTS

    Versions
    • 2.1.12-stable-1
    • 2.1.12-stable-1build1
    • 2.1.12-stable-1build2
    • 2.1.12-stable-1build3
    • 2.1.12-stable-1ubuntu0.1
    Affected ranges
    • ECOSYSTEM: < 2.1.12-stable-1ubuntu0.2

    Update to 2.1.12-stable-1ubuntu0.2

  • libevent Ubuntu:24.04:LTS

    Versions
    • 2.1.12-stable-9
    • 2.1.12-stable-9ubuntu2
    • 2.1.12-stable-9ubuntu2.1
    Affected ranges
    • ECOSYSTEM: < 2.1.12-stable-9ubuntu2.2

    Update to 2.1.12-stable-9ubuntu2.2

  • libevent Ubuntu:26.04:LTS

    Versions
    • 2.1.12-stable-10build1
    • 2.1.12-stable-10build2
    • 2.1.12-stable-10ubuntu0.1
    Affected ranges
    • ECOSYSTEM: < 2.1.12-stable-10ubuntu0.2

    Update to 2.1.12-stable-10ubuntu0.2

Original sources

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