Malicious PDF — malware analysis report

Static analysis result for SHA-256 91a17ca4f08f1c47…

MALICIOUS

PDF

73.0 KB Created: 2021-03-14 17:15:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 49cef42fa24101dd0215a49507518351 SHA-1: d2d70e8b8482cbe3d32955e7f1dc21f873e10510 SHA-256: 91a17ca4f08f1c476fb6295de202bbe724153cbf8770819cbad6fdba3ef3c3b6
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, many hosted on disposable domains, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the exploitation of PDF vulnerabilities or social engineering to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://lozipotod.ru/123?utm_term=cen-+tech+digital+multimeter+owners+manual PDF link annotation
    • https://zodaribidibukez.weebly.com/uploads/1/3/4/7/134716266/gasofow.pdfIn PDF document text
    • http://gixelube.iblogger.org/bezier_spline_sketchup_plugin_free.pdfIn PDF document text
    • https://pawomasa.weebly.com/uploads/1/3/4/7/134737305/0ce377cc9d4bd.pdfIn PDF document text
    • https://wavenugila.weebly.com/uploads/1/3/4/8/134852162/cf8cd.pdfIn PDF document text
    • http://nibofope.66ghz.com/acer_aspire_v5_571p_wifi_driver.pdfIn PDF document text
    • http://gudokevuxowa.22web.org/79578239626.pdfIn PDF document text
    • https://tazuwadafif.weebly.com/uploads/1/3/4/8/134857375/05fc21bb.pdfIn PDF document text
    • https://fujazilumekopel.weebly.com/uploads/1/3/2/6/132681311/firizeniluged.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://lilorubetu.epizy.com/95229581483.pdfIn PDF document text
    • https://d6b7b3c7-8429-4d82-9d75-5d5d09e763cc.filesusr.com/ugd/a8c229_43f2f8c7b4d54397bbcc716bef9cc7ca.pdf?index=trueIn PDF document text
    • https://b7eb3c74-9f10-4efd-a612-efb7ea03662f.filesusr.com/ugd/7198c1_b4630d8d001d443a82fa32395256b86b.pdf?index=trueIn PDF document text
    • http://vemesedesalo.rf.gd/76834798898.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/daaaf3e8-a13c-4632-9291-ca28b26532c2/josidasunagidudaxeliwege.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4e49270-843a-440c-a607-beb968173be8/rabidejatozevatugofa.pdfIn PDF document text
    • https://e97408dc-4b05-4e3b-9f19-f4127feb49ef.filesusr.com/ugd/a42eed_003329f992784862836b92af53bb8dcd.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4bd82631-c3af-4d9d-8fa8-2b66a7dc013b/nulodijodemidajulat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ce8e508d-3f8f-4221-896b-75b402149cda/honda_lawn_mower_repairs_melbourne.pdfIn PDF document text
    • http://pevivudawof.epizy.com/piccadilly_line_map.pdfIn PDF document text
    • http://kunaraxanoxun.epizy.com/hyperphosphatemia_guidelines_uk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1443347c-d34c-4ff2-9d1c-595dcb28d204/shell_script_command_line_arguments_count.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/01eb409d-e8d6-43e5-9ada-02d0a75ff635/free_download_hp_laserjet_p3015_printer_driver_for_windows_xp.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d81e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD81E 5384 bytes
SHA-256: 80886c6b2d716f572c630689f5696034e9ca42c0a7d51908309d4eb8a46ea586
font_01_sfnt_off0000ea55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA55 13192 bytes
SHA-256: 091751b0965aca6e95fccc7d8f5b5f050b9e29a023c3394cf822d9c3b7b4ba72