CVE-2026-112021 (GCVE-0-2026-112021)
Vulnerability from cvelistv5
Published
2026-10-18 11:38
Modified
2026-10-19 16:05
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
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-122 - Heap-based Buffer Overflow
Summary
snac2 before 2.93 contains a heap-based buffer overflow vulnerability in _xs_json_load_lexer() that allows unauthenticated remote attackers to corrupt heap memory by sending JSON strings containing a \u0000 escape. Attackers can send a single crafted application/activity+json POST to activitypub_post_handler(), which parses it before signature checks, overflowing heap allocations and crashing the server.
References
Impacted products
Vendor Product Version
grunfink snac2 Version: 0   < 2.93
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