Malicious PDF — malware analysis report

Static analysis result for SHA-256 87665b8be405c377…

MALICIOUS

PDF

83.0 KB Created: 2021-09-13 23:25:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7b423abb5104ea40a03c9494f5325d79 SHA-1: ec8bc97c1cd543e562d5c5aebe5fe698a009e76b SHA-256: 87665b8be405c3775d791771a6d80f0adbb4c00ed881c0cce2dcb1c2f14d2c4b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external domains, many of which are associated with link farms or disposable hosting, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were directly extracted, the PDF structure and embedded links are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pistant.ru/uplcv?utm_term=how+to+restore+sd+card+data+on+android PDF link annotation
    • http://flashdisplay.net/UploadFiles/FCKeditor/20210907033523.pdfIn PDF document text
    • http://getwealthythisyear.com/ckfinder/userfiles/files/68313134333.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/44849089577.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/18859014252.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/76966968648.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/zebinejonaxarenose.pdfIn PDF document text
    • https://atlaskvartir.ua/data/uploads/files/vokev.pdfIn PDF document text
    • http://aokisuper.com/ckfinder/userfiles/files/kenokixamefizusujiwimamo.pdfIn PDF document text
    • http://sake-tori.com/images/library/File/67528005028.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/3280778765.pdfIn PDF document text
    • https://peisheng.org/uploads/ckfiles/files/613a11061087f.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/nikuzijarirop.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/79394522779.pdfIn PDF document text
    • http://keifo.ru/ckfinder/userfiles/files/39373306906.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/42130796025.pdfIn PDF document text
    • http://cloverdiamond.com/file/jewud.pdfIn PDF document text
    • http://thaicockstar.com/ckfinder/userfiles/files/wixozopek.pdfIn PDF document text
    • http://culfordequestriancentre.org/UserFiles/file/mikuvekogagezupelabaduj.pdfIn PDF document text
    • http://koreadramatour.com/FileData/ckfinder/files/20210904_02C5CAB5358CC72C.pdfIn PDF document text
    • http://cl-pub.com/files/files/96564478358.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/f8db296e586bded0f156abccc46c30f5/basukunevenojebevixogeve.pdfIn PDF document text
    • http://hilimall.ae/uploads/files/27184662846.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f78c6bac48---busituzaropefadakafuwaru.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_off0000e045.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE045 10396 bytes
SHA-256: dba489bebb6c3cd263e3b07409491a5d27186f5d66dcc50fe9faebc1d12e2e4c
font_01_sfnt_off0000f7f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11009 17720 bytes
SHA-256: ec6af89944e5965583b913606a73ec49fd2a532c9925a90a74608d2770aeef4d