Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fba9472e8800477…

MALICIOUS

PDF

68.3 KB Created: 2021-09-27 06:29:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 9fa3d49b1250c0998488fce6742644a1 SHA-1: d9841c5523aca1bf4fb04b8d67f2dbf562d7af45 SHA-256: 3fba9472e8800477f54e85068f1c2484e2afb73e831ad63024e33a205c784353
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting an attempt to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the URLs and the PDF structure suggest it is designed to facilitate the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=download+maskgun+mod+apk PDF link annotation
    • http://lehnerkom.de/images/uploaded/file/42072042482.pdfIn PDF document text
    • https://ceylanotel.com/firma/files/37996673050.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1613d9c3375485---xelunafofenujadoketebif.pdfIn PDF document text
    • http://hotelrealerimini.it/userfiles/files/48264719425.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161429bec79621---31318865942.pdfIn PDF document text
    • http://uniquecharacters.com/upload/files/84040255850.pdfIn PDF document text
    • https://medpressa.ru/files/file/sinesedutoxobixasigijalof.pdfIn PDF document text
    • http://hailiaquatic.com/UploadFiles/file/jizadorosonugebiwaromegi.pdfIn PDF document text
    • http://livelyway.com/ckfinder/userfiles/files/lorewixoxabikebewabixujo.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/motunevix.pdfIn PDF document text
    • http://yonseri.org/userfiles/files/74508167975.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/liwotoj.pdfIn PDF document text
    • http://www.immo-uno.com/ckfinder/userfiles/files/zalipesikizamir.pdfIn PDF document text
    • http://esebtekstil.com/resimler/files/fiduxevoboxuja.pdfIn PDF document text
    • http://lnianemarzenie.pl/userfiles/file/fibavamajavaburadoguvan.pdfIn PDF document text
    • http://rakkhunnursinghome.com/user_img/files/49387316094.pdfIn PDF document text
    • https://eghamatyab.com/basefile/bainbookcom/files/17685344041.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/06be99f3bb7dfc041e9cac3293fc1673/tovavanegu.pdfIn PDF document text
    • http://go-pxl.com/uploads/files/gejuwezudevasev.pdfIn PDF document text
    • http://kechengchem.com/upload/files/laranob.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013new/admindia/ckfinder/userfiles/files/91379906479.pdfIn PDF document text
    • http://www.bc-arman.kz/ckfinder/userfiles/files/22226620010.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_off0000ad5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c570.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC570 15108 bytes
SHA-256: 5d6a1a82055fb7a12ac3818d6aa1979bf8dd0f31d521218dfce8ce21f2a346ec
font_02_sfnt_off0000ec16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC16 10592 bytes
SHA-256: 881e3e63a82020721045bf703b0508ca819c8e61cefc26e42b0ffcdfffce7ef8