Malicious PDF — malware analysis report

Static analysis result for SHA-256 988acea81ee9b5ba…

MALICIOUS

PDF

82.3 KB Created: 2021-09-17 14:08:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 36fd03038129eb16018e1165e5dd8d59 SHA-1: 1fa6f366fb1115baac351970769b287305e777ea SHA-256: 988acea81ee9b5ba500d6eba4840779854f61d0ccf11bf215c7c74443c082ae5
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware sites. Although no scripts were directly extracted, the PDF structure and URL patterns suggest exploitation for client execution, potentially via embedded JavaScript or a vulnerability.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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.
  • 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://cepatdaftargroup2.com/contents/files/vivojin.pdf In PDF document text
    • https://perfecthospital.org/FCKeditor/file/lusefubijaripofam.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/41391423261.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/11989104883.pdfIn PDF document text
    • https://kildevangen.dk/files/saroripevoweremadojaxo.pdfIn PDF document text
    • http://strandedtattoo.com/file/pilelenulid.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/jusenuzodod.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/56011178709.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/mutomirafukotonajus.pdfIn PDF document text
    • https://lmcmanager.com/ckfinder/userfiles/files/39248743308.pdfIn PDF document text
    • http://gojjang.com/uploads/files/18041140833.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/161365dc325268---58334411490.pdfIn PDF document text
    • https://inwestorfinanse.pl/userfiles/file/botisenebigufasuv.pdfIn PDF document text
    • http://trieuduong.com/images/Download/beduf.pdfIn PDF document text
    • http://rc-saty.cz/gais/image/file/65085427672.pdfIn PDF document text
    • http://xn--j1aii.su/userfiles/file/26902906622.pdfIn PDF document text
    • http://www.radanhorse.com/resource/files/fanapenedob.pdfIn PDF document text
    • http://kvarkeno56.ru/userfiles/file/6069289820.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161414d8952771---dusupikakixitomapuduxivat.pdfIn PDF document text
    • http://studiobaldizzone.com/userfiles/files/nexefizowopavujekesisox.pdfIn PDF document text
    • https://onecre.com/images/content/files/nokotojilexefe.pdfIn PDF document text
    • https://panificioilcavaliere.it/userfiles/files/nimizagebubasifojo.pdfIn PDF document text
    • https://inoxquochoang.com/app/webroot/files/images/pages/files/92114258608.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/jexibexisapovufekuxizezas.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/ruzinepiletudejokaxop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=demon+slayer+infinity+train+full+movie+english+dubPDF 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_off0000d656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD656 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6D 11220 bytes
SHA-256: 4a031f7df2004eadadbec2e7a86b9e1072e12891a30d51371c68f334f628f9bb
font_02_sfnt_off00010856.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10856 19540 bytes
SHA-256: 7cdb02ab0d5bcf7ae9703cb11bff51db10f7f44653554fb4f12d52352f6fc28a