Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51abfcbce2d16bc…

MALICIOUS

PDF

86.6 KB Created: 2021-09-18 02:31:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 9b10e25929fd24555b3bb0b25cc932fb SHA-1: 1dfd3832f5f2aee79d1b5cdd26db25b0ced341c3 SHA-256: b51abfcbce2d16bc57534871f505c7a935d4726643650ab64818d0f4207be575
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and multiple external URIs, indicating an attempt to redirect the user to malicious content or download further payloads. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of a download button lure reinforces the malicious workflow.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crysiq.ru/uplcv?utm_term=sausage+man+apk+pubg PDF link annotation
    • http://gz-chengeng.com/uploadfile/files/tudesonebejixexulopon.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/34216399184.pdfIn PDF document text
    • http://cattaneoarchitetti.it/userfiles/files/43612714338.pdfIn PDF document text
    • https://rimi.sk/userfiles/file/80197041266.pdfIn PDF document text
    • http://ropesadventure.com/d/files/kibekajufadew.pdfIn PDF document text
    • http://montagnobozzone.it/userfiles/files/58062712042.pdfIn PDF document text
    • http://yuanjiangchem.com/upload/files/69225891449.pdfIn PDF document text
    • http://homeopathyhk.com/files/vigiginiledap.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/7lj8p24lrqotj12taq86eurfv0/96225597947.pdfIn PDF document text
    • https://peterdegendt.be/file/retexanobepin.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/fedomebuvube.pdfIn PDF document text
    • https://henuopack.com/d/files/635824966.pdfIn PDF document text
    • http://dj-maily.com/uploads/pages/files/15722283417.pdfIn PDF document text
    • http://tipkeo.com/js/ckfinder/userfiles/files/13443799464.pdfIn PDF document text
    • https://www.asoriofrio.org/ckfinder/userfiles/files/makivorelade.pdfIn PDF document text
    • http://mikol-styl.cz/userfiles/file/jobesagubafeludizuzuvimab.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109080945416706.pdfIn PDF document text
    • https://goodline.by/userfiles/file/falojapama.pdfIn PDF document text
    • http://swhos.com/upload/files/81927385667.pdfIn PDF document text
    • https://fobh.net/userfiles/files/bexidisunura.pdfIn PDF document text
    • http://excitechem.com/userfiles/file/giwopegeluxabaleleboj.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/fubefazoxexopogefel.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/ximujenirawawuwutubek.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/gugumeluxu.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143881499bd2---ralil.pdfIn PDF document text
    • http://www.jysunshine-hotel.com/up_files/file/72740231575.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_off0000ea9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA9C 10544 bytes
SHA-256: 2343a9a833da3a752dee13b14df2f5d7acdbddfe95f8085dcdd47a546d7dbde3
font_01_sfnt_off0001025b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1025B 19620 bytes
SHA-256: 3c961795e1ddd13b69d917bab3d083e7b5bf53aaeda4ac8bc7f49f05a2b4eb82
font_02_sfnt_off0001352c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1352C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1