Vulnerability · Published Aug 10, 2026 · Assigned by CERT-PL
CVE-2026-18370Heap-based buffer overflow in entr
Medium 4.8
In plain English
A medium-severity heap buffer overflow in entr from eradman. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities).
Official description
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
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | entr | no fix listed | DEBIAN-CVE-2026-18370 |
| Debian:13 | entr | no fix listed | DEBIAN-CVE-2026-18370 |
| Debian:14 | entr | no fix listed | DEBIAN-CVE-2026-18370 |
| Ubuntu:22.04:LTS | entr | no fix listed | UBUNTU-CVE-2026-18370 |
| Ubuntu:24.04:LTS | entr | no fix listed | UBUNTU-CVE-2026-18370 |
| Ubuntu:26.04:LTS | entr | no fix listed | UBUNTU-CVE-2026-18370 |
| Ubuntu:26.10 | entr | no fix listed | UBUNTU-CVE-2026-18370 |
Affected products (as reported)
Weakness: CWE-122 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N