CVE-2026-35369 is a medium-severity (CVSS 5.5) Improper Input Validation vulnerability in uu_kill. A fix is available for uu_kill — see the affected versions and patch details below.
uutils coreutils kill System-wide Process Termination and Denial of Service via Argument Misinterpretation
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-35369.
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.
How urgent is this, really
CVE-2026-35369 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
uu_killReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
kill -1 is incorrectly parsed as a positional pid = -1; combined with the default SIGTERM this calls kill(-1, SIGTERM), signaling nearly every process the caller can see. GNU kill recognizes -1/-9 as signals and reports "not enough arguments".
$ kill -1 # uutils: kill(-1, SIGTERM) -> mass termination / crash
$ kill -1 # GNU: kill: not enough arguments
Impact: a user running kill -1 mass-terminates processes, potentially crashing the system. Recommendation: parse -N as a signal number, and error with "not enough arguments" when no PID is given.
Remediation: Acknowledged by Canonical; fixed in commit cae94028.
Reported by Zellic in the uutils coreutils Program Security Assessment (prepared for Canonical, Jan 20 2026), audited commit 3a07ffc5a9bd4c283e75afa548ba1f1957bad242. Finding 3.70. Credit: Zellic.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | uu_kill | all versions | 0.6.0cargo update -p uu_kill --precise 0.6.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for uu_kill, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update uu_kill to 0.6.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-35369 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-35369 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-35369. 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-2026-35369 in your dependencies?
O3 Security finds CVE-2026-35369 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.