CVE-2025-12875
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
A weakness has been identified in mruby 3.4.0 affecting the ary_fill_exec function in mrbgems/mruby-array-ext/src/array.c. Manipulating the start/length arguments can lead to an out-of-bounds write. The attack requires local access, the exploit is publicly available, and the fix is commit 93619f06dd378db6766666b30c08978311c7ec94.
Risk Assessment
A local attacker can use the publicly available exploit to perform an out-of-bounds write, potentially leading to a crash or code execution.
Recommendation
Apply patch 93619f06dd378db6766666b30c08978311c7ec94 or upgrade mruby to a version containing this fix.
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A NULL pointer dereference vulnerability exists in the Prism parser component of mruby 4.0.0. An attacker can provide a specially crafted Ruby source file that triggers the parser to pass a NULL pointer to string handling functions, resulting in undefined behavior and application crash.
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A flaw has been found in mruby 3.1.0. The function udiv in bigint.c is affected. Executing a manipulation can lead to floating point comparison with incorrect operator. The attack can be launched remotely, and the exploit has been published.
- CVE-2025-13120Medium
In mruby up to 3.4.0, the sort_cmp function in src/array.c contains a use-after-free vulnerability that can be exploited locally. The exploit has been publicly disclosed.
Original NVD description (English source)
A weakness has been identified in mruby 3.4.0. This vulnerability affects the function ary_fill_exec of the file mrbgems/mruby-array-ext/src/array.c. Executing a manipulation of the argument start/length can lead to out-of-bounds write. The attack needs to be launched locally. The exploit has been made available to the public and could be used for attacks. This patch is called 93619f06dd378db6766666b30c08978311c7ec94. It is best practice to apply a patch to resolve this issue.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS