CVE-2026-63383 (GCVE-0-2026-63383)

Vulnerability from cvelistv5 – Published: 2026-08-20 17:48 – Updated: 2026-08-20 18:41
VLAI
Title
Libevent: decode_tag_internal() can lead to out-of-bounds read
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.
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
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 18:37 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
libevent libevent Affected: >= 2.2.0-alpha, < 2.2.2-alpha
Affected: < 2.1.13
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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