Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d8443a9e7571ba5…

MALICIOUS

PDF

93.5 KB Created: 2021-09-16 12:34:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 71017e402dfbcd7c66c6b4a3c5c835f1 SHA-1: 92485a4eaff9397ae03b6f5bff91708463966f6b SHA-256: 1d8443a9e7571ba57853f7a81e22aba19ea2b5483e47e0d0850841e7656d1a9f
126 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains a large number of external links, many of which are on disposable domains and utilize UTM parameters, suggesting a phishing or link-farming campaign. While no scripts were explicitly extracted, the PDF structure and numerous external URIs point towards a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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 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://laborke.ru/uplcv?utm_term=famous+five+2+pdf PDF link annotation
    • http://sjzhtchem.com/upload/files/wufotezu.pdfIn PDF document text
    • http://vanprodukt.cz/UserFiles/File/nonovoxus.pdfIn PDF document text
    • http://hnkingdee.cn/Files/file/202196175058.pdfIn PDF document text
    • https://agregadoschucuri.sinecsas.com/ckfinder/userfiles/files/mujolonafifegife.pdfIn PDF document text
    • http://precedent.by/_newsite/images_from_html_editor/file/wilaninegetisox.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/95346128541.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/bilapeviwedemuve.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210912_3D02256A928D94FB.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/zixopuzuvifutuvug.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/9202585406.pdfIn PDF document text
    • http://mrpokedb.com/uploads/files/58473909497.pdfIn PDF document text
    • http://ktcz.eu/files/files/78307380122.pdfIn PDF document text
    • http://defhjdrjioo.friend-match.com/upload/files/49456076065.pdfIn PDF document text
    • https://bartonsteel.com/tony/barton/ckfinder/userfiles/files/78004015046.pdfIn PDF document text
    • https://eijo.in/ckfinder/userfiles/files/80404360287.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/vatekedaxununozazawinamo.pdfIn PDF document text
    • http://huzatfokozo.hu/editor_up/gekuzavalalofo.pdfIn PDF document text
    • https://rivieresoceanie.com/userfiles/file/kifuvigeta.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/8455937769.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/mifabax.pdfIn PDF document text
    • http://apnschool.in/singhania/downloads/file/12204526188.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614034c35189c---gojavumizalegajokufe.pdfIn PDF document text
    • http://storemisr.com/uploads/files/tenetuwijesa.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_off00010586.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10586 19508 bytes
SHA-256: 28d745899ce2f8416da97e6116cb61e822741de8c48f8c7ef49a722fefb36fa4
font_01_sfnt_off00013884.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13884 10572 bytes
SHA-256: a902311e72280a8c9b9111792d6eaa5255602759c33f0738b6bc1f3c93f7d135
font_02_sfnt_off000150bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1