CVE WatchAug 20, 2026

CVE-2026-63381

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free in buffer.c when evbuffer_add_buff

CVSS

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No CVSS

EPSS

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KEV

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Exploit Today

0-100

Published: Aug 20, 2026 · Last modified: Aug 20, 2026 · CWE-908

EPSS · 30d

Not enough EPSS history yet.

Technical description

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free in buffer.c when evbuffer_add_buffer_reference processes an output buffer whose out_total_len is zero. evbuffer_free_all_chains frees the initial empty chain without resetting outbuf->first, outbuf->last, or outbuf->last_with_datap, and APPEND_CHAIN_MULTICAST subsequently dereferences the dangling chain pointer. A caller that can drive this buffer state can cause memory corruption or a process crash. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

Official references

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