Malicious PDF — malware analysis report

Static analysis result for SHA-256 b933d8cea6a80858…

MALICIOUS

PDF

72.8 KB Created: 2021-09-22 21:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 21a9f100a7984ba2fdc8fabf6999f751 SHA-1: 74c976a300ae9302b399c13247512f37b23a102c SHA-256: b933d8cea6a80858ab215b6b6f70ccfbadcdcc7c97c2a8aafba041f8b8ecef4f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious sites, likely for credential harvesting or malware download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://sca-eagleegg5k.com/ckfinder/triplebuserfiles/file/89030846758.pdf In PDF document text
    • https://icon-studios.com/userfiles/file/96483431021.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/meriwanulumab.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/wovaraf.pdfIn PDF document text
    • http://ettermanenterprises.com/ckfinder/userfiles/files/ziwedasetorowa.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021091517382773499.pdfIn PDF document text
    • https://cuatudongbinhduong.net/uploads/files/98820451643.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/10086548198.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/burozojipupatagi.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/97660916349.pdfIn PDF document text
    • http://emirates-offshore.com/uploads/image/file/99998416221.pdfIn PDF document text
    • http://dhf-china.com/d/files/11022511116.pdfIn PDF document text
    • http://xn--80aafbkbafwdti1ahihccrg.xn--p1ai/pict/file/27338605536.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/60092177250.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/69635611630.pdfIn PDF document text
    • https://kanalprofi.at/UserFiles/file/voxepizur.pdfIn PDF document text
    • https://szallas-karpatalja.hu/upload/78592351315.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/jufupubimoseb.pdfIn PDF document text
    • https://mgrenginiai.lt/ckfinder/userfiles/files/41882900117.pdfIn PDF document text
    • https://erdemlerkoleji.com/resimler/files/20585337769.pdfIn PDF document text
    • http://ilkjv.com/Images/Media/files/jamulubafidu.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/nokekavumibaboxemijozutit.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16143fd8410a8b---govisi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+use+linearlayout+in+android+studioPDF 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_off0000bc57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC57 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d469.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD469 15964 bytes
SHA-256: a23fe638c81e3133131335d0b20522f05fff4951b887ab4eda829f890206e7a6
font_02_sfnt_off0000fda2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA2 10532 bytes
SHA-256: 0283049be36d70d7a17e52f15a48a0a003a05097067b7079cfed84f194fb5fb8