Malicious PDF — malware analysis report

Static analysis result for SHA-256 63db74571036e956…

MALICIOUS

PDF

81.8 KB Created: 2021-09-18 02:59:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 76aaf4918d04658f685b83a234ff1153 SHA-1: 8c70114f8e9bc1f38126144a55b5824f69b540b0 SHA-256: 63db74571036e956ebb8ec4493b38b30f64219c2753dd2716c1e2229effb971c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, including one pointing to 'synerhu.ru' with a 'mp3 studio apk' UTM term, suggests a phishing or malware distribution attempt. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating the PDF is part of a link farm designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://synerhu.ru/uplcv?utm_term=mp3+studio+apk PDF link annotation
    • http://makinsushi.com/uploads/files/43897211621.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142f029c221e---95675924369.pdfIn PDF document text
    • http://seoulgreeter.com/userData/board/file/nelixuf.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/budawifekobob.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/guxabadejemakuziwoweb.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/76871388133.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/95216025382.pdfIn PDF document text
    • http://www.agot.pl/upload/file/nonotojojeg.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/molobituvakemuwinirip.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133c177079d9---70775910227.pdfIn PDF document text
    • http://support-cmu.com/filedata/file/61332201757.pdfIn PDF document text
    • http://ats-dz.com/userfiles/file/weritoxabevedigozozaxet.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/xaxusebajijomelat.pdfIn PDF document text
    • http://tmacfashion.com/ckfinder/userfiles/files/dowipewad.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/8632748490.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/46179799332.pdfIn PDF document text
    • https://kawanmto.com/contents/files/woruzivipubaketejajome.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/54836400957.pdfIn PDF document text
    • http://tekizolasyon.com/ckfinder/userfiles/files/72954719032.pdfIn PDF document text
    • http://profesniprukaz.cz/ckfinder/userfiles/files/vezalomutem.pdfIn PDF document text
    • http://veszpremkosar.hu/_user/file/80196131651.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/15225335192.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/sagubowibin.pdfIn PDF document text
    • http://msinziniering.com/userfiles/file/13541258919.pdfIn PDF document text
    • http://obkladacstvikolar.com/content/78326375286.pdfIn PDF document text
    • https://bczenekar.hu/files/file/47747495953.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_off0000d7a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A2 10360 bytes
SHA-256: 2fd704a7da9890655ed31b5a7f13f765b26c597557e8d531361f5090b3840ff5
font_01_sfnt_off0000ef37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF37 19240 bytes
SHA-256: 009c3dbbb3daa0d9766cfb7c459c27f7dacb423156517cfc2929cfbee94e625b
font_02_sfnt_off000121a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1