Malicious PDF — malware analysis report

Static analysis result for SHA-256 6efe4ed25fe845ee…

MALICIOUS

PDF

73.8 KB Created: 2021-09-16 22:45:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0aed8783c5494b241cdfa4a20d645c3d SHA-1: e196165f3758d7a4f825b9c70b76b4982618d2d2 SHA-256: 6efe4ed25fe845ee57e5846a90bfa35caacecc93339e3dfd3e9665112f51bb8f
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to a link farm hosted on disposable domains, a common tactic for phishing and scam operations. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious content, likely leveraging T1059.007 (JavaScript) for exploitation within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://sayurmateng.com/contents/files/nasupop.pdf In PDF document text
    • http://xn--o39a91gvwm83kbsn.net/FileData/ckfinder/files/20210907_B111DE73273A3C12.pdfIn PDF document text
    • https://lifecareproduct.in/ckfinder/userfiles/files/42293759387.pdfIn PDF document text
    • http://marathon-gexin.com/Uploadfiles/files/71376358370.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/woteladarelelemewe.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/fidudo.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/diwugisuromofobu.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/sexurifoge.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/76003761090.pdfIn PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/fumokikelofepexa.pdfIn PDF document text
    • http://simonkuehner.de/gfx/userfiles/files/91570187220.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/mg41slnoo2dv63nnhioh75lcct/9284384726.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/jibotewaluzevapufigumarap.pdfIn PDF document text
    • http://uhy-th.com/image/upload/files/sufugomulemagi.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/xosozijubojepokiguru.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/melopatadokapo.pdfIn PDF document text
    • http://monikaknoblochova.com/userfiles/file/nejatipebute.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021091002533192.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/d0d090527d937b4a2a7277daa598ff95/91906799901.pdfIn PDF document text
    • http://baoveantam.info/upload/files/32952790872.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/52459335029.pdfIn PDF document text
    • http://jlicentral.com/images/authors/file/dusuluxazobut.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109092052104959.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/lutaxopazifo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=best+indie+game+of+2020PDF link annotation
    • 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_off0000be44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD656 16452 bytes
SHA-256: ed350f023edac29eab224e0a1854ef780b64cf7cf89518317d383a53b3cd6dd9
font_02_sfnt_off00010100.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10100 10848 bytes
SHA-256: 6073047a174aad9b67884ac4066c85e049f4f3a37a266b852e207e38bf4ff179