CVE-2026-18370
MediumCVSS 4.8Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
entr is vulnerable to a heap-based buffer overflow in run_utility() due to incorrect size calculation using strlcpy(), which can lead to memory corruption and process abort.
Risk Assessment
A local attacker can cause process crashes and denial of service, and in extreme cases memory corruption, potentially enabling further attacks.
Recommendation
Update entr to a version containing the fix (commit 2467fe0) and avoid running entr with untrusted arguments.
Original NVD description (English source)
entr is vulnerable to Heap-based buffer overflow in run_utility() function. The function allocates a fixed-size heap buffer using malloc(ARG_MAX) and copies command-line arguments into it. It advances the destination pointer based on the return value of strlcpy(), which returns the total length of the source string rather than the number of bytes written. When the buffer is exactly filled, the remaining size underflows as an unsigned size_t, causing subsequent copies to write out of bounds. This can be triggered by supplying command-line arguments whose combined length fills the buffer, or via the /_ substitution feature which expands a short token into a longer pathname at runtime. The local attacker can cause memory corruption, process abort, and denial of service. This issue was fixed in commit 2467fe0