Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9f7c588fde0185a…

MALICIOUS

PDF

89.0 KB Created: 2021-09-24 11:36:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 238fa5a0db2c063d44b8bfc6a796c13f SHA-1: 3b815fa293e4fdbde6ec4cc075e6f1458e16126f SHA-256: d9f7c588fde0185a38a7a94091d7680c6b13f6cc2f2298eac529a618d433e7e6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external websites, characteristic of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to lure users to malicious sites, likely via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://infrive.ru/uplcv?utm_term=android+app+with+node+js+backend PDF link annotation
    • http://goldartline.ua/userfiles/file/34790770714.pdfIn PDF document text
    • http://kernenshepler.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/penibaso.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/3148595472.pdfIn PDF document text
    • http://www.waetsukai.jp/system/ckfinder/userfiles/files/75598882238.pdfIn PDF document text
    • https://hongdung.vn/ckeditor/images/files/zizimobajukinadekipage.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/44971758757.pdfIn PDF document text
    • http://bannhuaduong.net/upload/files/58873347304.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/34907578806.pdfIn PDF document text
    • https://pass-eco-energies.com/ckfinder/userfiles/files/86641388084.pdfIn PDF document text
    • http://www.globalnautique.nl/upload/files/gunejajakufeme.pdfIn PDF document text
    • http://nikolalepojevic5.com/multimedia/file/bunovilijabesopemavukotu.pdfIn PDF document text
    • https://kitchensofdiablo.com/upload/file/41992156394.pdfIn PDF document text
    • http://importfoodfair.com/userfiles/image/2021/09/file/74917210889.pdfIn PDF document text
    • http://fresh-j.info/images/uploadedimages/file/64235312526.pdfIn PDF document text
    • http://polletnv.be/uploads/files/36617149932.pdfIn PDF document text
    • http://varosom.hu/userfiles/files/paratukibemele.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161320093b2b2a---sonedomusaxogo.pdfIn PDF document text
    • http://studiorestagno.eu/userfiles/files/51038472262.pdfIn PDF document text
    • http://ohsongpharm.com/ckfinder/userfiles/files/kuxinolowigif.pdfIn PDF document text
    • https://tdemo.order-pro.com/ckfinder/userfiles/files/lumezenitizepeku.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/ramapugi.pdfIn PDF document text
    • http://nhasachnguyenvancu.com/Images_upload/files/35352348817.pdfIn PDF document text
    • http://proart.by/media/file/80295633639.pdfIn PDF document text
    • http://alacarte-husum.de/userfiles/file/96555485906.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b3ad582c5---fifajaparevimemitaxu.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f363.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF363 10992 bytes
SHA-256: fdb1f8e17d23e17b21d3f35d10ec4a3bb5d5eb6af4a6ddeadaa6af98aa7a6fdc
font_01_sfnt_off00010caf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAF 18932 bytes
SHA-256: ac3e0e208bd3f3c82099cf6b8c14694bdcb2394d31b36091ba40f1b0087f7498
font_02_sfnt_off00013e82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1