Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e71b9393b429585…

MALICIOUS

PDF

81.3 KB Created: 2021-09-21 05:11:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 34253d183f2d382c5dc7855b3a326f14 SHA-1: 09f39f737d27574eb57b5e74029cc065dfe9434b SHA-256: 9e71b9393b429585a5547b171d98571329326106b66159571e6badf96383e9d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, forming a link farm. Heuristics indicate this is a phishing or malware distribution attempt, with ClamAV specifically flagging it as 'Pdf.Phishing.Trojan'. The ML classifier also strongly indicated maliciousness. While no scripts were directly extracted, the PDF structure and embedded links are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://chcial.ru/uplcv?utm_term=ide+android+java PDF link annotation
    • http://epilia.com/upload/FCKEditorfile/67360118716.pdfIn PDF document text
    • http://rowerowaszkola.pl/imgturysta/files/16310703102.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/dfdc65d62ee234d32c1b59fc618320c6/sanenilugogew.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/73291531560.pdfIn PDF document text
    • http://smwiarus.pl/ckfinder/userfiles/files/10508933519.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210903_3C6E1E2E58BB5BDF.pdfIn PDF document text
    • http://tvcsoltau.de/userfiles/file/sujewoba.pdfIn PDF document text
    • https://fond.ru/userfiles/file/dozifivusinibagevusesakan.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613169a87a339---88413982910.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/48577869443.pdfIn PDF document text
    • http://bighost.vn/uploads/userfiles/file/85978420981.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614467db6e737---wurasaboseposudofudodux.pdfIn PDF document text
    • http://inspiredindianfoundation.org/uploads/42789157059.pdfIn PDF document text
    • http://remproekt-m.ru/admin/ckfinder/userfiles/files/89130048679.pdfIn PDF document text
    • http://anm-av.de/uploads/files/xadibapexakuxoxulitakopi.pdfIn PDF document text
    • http://hoangminhphatkorea.com/webroot/img/files/27204039813.pdfIn PDF document text
    • http://thaifilmind.com/UserFiles/file/94809328788.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/4873564598.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/luxupewifavaz.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/jilolufud.pdfIn PDF document text
    • https://kligi.viart.lt/ckfinder/userfiles/files/jisutizimolonejosipawurif.pdfIn PDF document text
    • http://stimatacasa.eu/userfiles/files/fakupalabo.pdfIn PDF document text
    • http://ydtmuhendislik.com/ckfinder/userfiles/files/85548930284.pdfIn PDF document text
    • https://lbjgold.in/ckfinder/userfiles/files/64117122262.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_off0000d779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD779 19016 bytes
SHA-256: c5a9c2bafc95df50f0557bd530f51166799753007504197d77d3af51cf708b2f
font_01_sfnt_off00010987.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10987 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001219e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1219E 10076 bytes
SHA-256: 394dd2884dc68d9778fcec601610cf6ecf31a349dbb541111aa679fa9fa8ef27