Malicious PDF — malware analysis report

Static analysis result for SHA-256 8db94d869a16cb0b…

MALICIOUS

PDF

77.0 KB Created: 2021-09-30 16:58:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 86441c960245877b5f3255c986a8f4e6 SHA-1: 7cc524210a6512317c90d91324b0cf657076dbda SHA-256: 8db94d869a16cb0b2e75f14f54c1d94e6a44b2cefded35f63645680f5a7e5b88
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised CMS upload directories, suggesting it functions as a link farm or a lure to phishing/malware sites. The PDF structure and embedded URLs are consistent with phishing campaigns that use malicious documents as attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://oniceh.ru/uplcv?utm_term=assoluto+racing+offline PDF link annotation
    • http://bielle-srl.com/userfiles/files/41180875041.pdfIn PDF document text
    • https://mmoxx.mn/userfiles/files/77759360970.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/6030219afdfa1c7206b0b1855185a4f2/91422899520.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/kabak.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/3d43464aa27b3ce93938a513fde45316/vepuwelaja.pdfIn PDF document text
    • http://fibertechnique.com/tmp/file/rovuzalatiketamabev.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/6806723973.pdfIn PDF document text
    • https://razredna-nastava.net/files/verarimuzavipimezijazamu.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/35240311800.pdfIn PDF document text
    • http://studiodebiaggi.eu/userfiles/files/kusazusinexaduror.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/fobadatajelusuzeni.pdfIn PDF document text
    • http://tuning-zone.eu/userfiles/file/sijorabipemajeferu.pdfIn PDF document text
    • https://reazfarah.com/ckfinder/userfiles/files/sobaredugugolefasuval.pdfIn PDF document text
    • http://rkenterprisesonline.com/FCKeditor/file/1602953050.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/7d993b0f65c91aa05cd3ccbb3f2b2e1b/zizulanig.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16141aa2606bbe---40514106476.pdfIn PDF document text
    • https://aksusu.com/upload/files/56989038655.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/56204881585.pdfIn PDF document text
    • https://www.educationsexuelle-ecole.ch/ck/ckfinder/userfiles/files/fifumavuladi.pdfIn PDF document text
    • http://bajkolandia-leszno.pl/userfiles/file/gemovafafimiwu.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/dapifonorusot.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/94374946602.pdfIn PDF document text
    • http://brilsports.ro/userfiles/file///36716393304.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_off0000c2a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2A8 19580 bytes
SHA-256: 82e584a41e4163a6dcaea75261481df29521c0ac85c99d82e794fecd2f22b7af
font_01_sfnt_off0000f5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FC 10592 bytes
SHA-256: 06697ad5bd6bf32464b32db4613303fdc9fee1ae3e04ee50ff37a01592ecddbb
font_02_sfnt_off00010e5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1