CVE-2026-35381
LOWA logic error in the cut utility of uutils coreutils causes the utility to ignore the -s (only-delimited) flag when using the -z (null-terminated) and -d '' (empty delimiter) options…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Description
A logic error in the cut utility of uutils coreutils causes the utility to ignore the -s (only-delimited) flag when using the -z (null-terminated) and -d '' (empty delimiter) options together. The implementation incorrectly routes this specific combination through a specialized newline-delimiter code path that fails to check the record suppression status. Consequently, uutils cut emits the entire record plus a NUL byte instead of suppressing it. This divergence from GNU coreutils behavior creates a data integrity risk for automated pipelines that rely on cut -s to filter out undelimited data.
Affected Products
coreutilsuutilsDetection & mitigation playbook
Vendor / applianceDetect
Inventory every uutils coreutils deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Fix
Apply the uutils coreutils security patch or hotfix for CVE-2026-35381 on the affected version, following the vendor advisory for your exact build.
Workarounds
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2026-35381 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2026-35381. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-35381 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2026-35381 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.