CVE-2026-63383 (GCVE-0-2026-63383)
Vulnerability from cvelistv5
Published
2026-08-20 17:48
Modified
2026-08-20 18:41
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
Summary
Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent can read beyond a contiguous evbuffer region in event_tagging.c when decode_tag_internal requests at most five bytes from evbuffer_pullup but iterates using the full logical buffer length. A fragmented evbuffer containing a six-byte malformed tag can therefore advance past the pullup window and trigger an out-of-bounds read, which can crash a process that decodes attacker-controlled tagged RPC data. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.
References
Impacted products
Vendor Product Version
libevent libevent Version: >= 2.2.0-alpha, < 2.2.2-alpha
Version: < 2.1.13
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