Malicious PDF — malware analysis report

Static analysis result for SHA-256 e399624c21bc57e5…

MALICIOUS

PDF

80.9 KB Created: 2021-09-03 22:01:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c5547f326e3721a6f2fef53cb3f0372b SHA-1: cac51da20df6697bb4393b167e0fc1fc28dbeeb7 SHA-256: e399624c21bc57e5671e60a48364f29e379805e93eff2dc4c4a7129c6af26d32
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to numerous external URLs, many hosted on compromised WordPress sites or disposable domains, suggesting an attempt to distribute malicious content or conduct phishing. The presence of embedded URLs and the nature of the link farm indicate a likely spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://medvor.ru/uplcv?utm_term=quipux+ecuador+manual PDF link annotation
    • http://www.plan.msu.ac.th/ckfinder/userfiles/files/58214893011.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/e69a44fae855d4ef9ec9cd425ea9a6db/36485901589.pdfIn PDF document text
    • https://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/misibefufuropo.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/f19b327a2e002b0f3a47a4609b7b5422/jobudibiju.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160975c22d0b6f---penekiragibok.pdfIn PDF document text
    • http://aptwash.com/userData/ebizro_board/file/fubutuvunidobilavugipavig.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/6bd5f8ed319c9228faf79a42c1b4a9f6/30321360787.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/f77b4cba1c4fde903c54a4def3ac75fa/80570112403.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869bcb96380---vujiporozew.pdfIn PDF document text
    • http://frutapacargentina.com/ckfinder/userfiles/files/mifajewizoromav.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609972b1545aa---lesikow.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/gijakaxuxudugedevoboj.pdfIn PDF document text
    • http://togul.org/sites/default/files/file/morada.pdfIn PDF document text
    • http://kperrylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/9576162114.pdfIn PDF document text
    • http://slp72.com/clients/7/7b/7b902bee17765b19ebdde6030f24742d/File/supenikomulogazegadajiri.pdfIn PDF document text
    • http://sziszolg.hu/editor_up/jojegises.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/51026283881.pdfIn PDF document text
    • https://dhcom.vn/userfiles/file/90104140066.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/16083b24bb6813---gasino.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/d4c4376ff86d8ebe247171937052a535/jabirokafidetediromilewif.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/wisugikujalaga.pdfIn PDF document text
    • http://pvvc.cz/files/gobipilemusuwoluganivor.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_off0000d58e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD58E 18596 bytes
SHA-256: 925937cbe88061f202ce3dcd0c9b87aed03ee31d27788e2d4adc6306b8c50e4a
font_01_sfnt_off00010581.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10581 10672 bytes
SHA-256: 50a78ef930838bae469a3f74da1523ab3e03d67feacbb7acc08b20780197baa0
font_02_sfnt_off00011df2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1