Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc495b827ef92d37…

MALICIOUS

PDF

105.0 KB Created: 2021-09-20 13:51:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 1812582599dee74a3605bae91e4cd078 SHA-1: fcdb5ffd37d72f0962f9f5628f82cdf79f3380b5 SHA-256: cc495b827ef92d3743a66b4316c3283c80e7bc22614596e0eba2bcc58665bdd1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which are part of a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic to distribute malicious content through a large number of seemingly unrelated domains. While no scripts were explicitly extracted, the presence of external URIs and the link farm structure strongly suggest an intent to redirect users to phishing or malware-hosting sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://culturasiapamplona.com/guiarte_userfiles/files/37946060682.pdf In PDF document text
    • http://pretaporter-pegah.com/userfiles/file/buxedabogiremad.pdfIn PDF document text
    • http://colleges-in-tamilnadu.com/FCKeditor/userfiles/file/bajiwupewipusi.pdfIn PDF document text
    • http://christ-china.com/filespath/files/20210920165928.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142d98d49f31---47897660666.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/wumukikigab.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/7107866881.pdfIn PDF document text
    • http://netart.hu/userfiles/file/37779824415.pdfIn PDF document text
    • http://kuppersbusch.hu/userfiles/files/zobovilorepinipojovedub.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf2349b409---renafale.pdfIn PDF document text
    • https://pianoinprimopianofestival.com/uploads/file/surekirujo.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/baten.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/dixowimemabanuwivez.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210907_940F7E9335DB2B9B.pdfIn PDF document text
    • https://harteron.ee/userfiles/file/kiwabigizolafepimowefaxe.pdfIn PDF document text
    • http://studiogalata.it/userfiles/files/disakasakoduge.pdfIn PDF document text
    • http://kubkao-kubpla.com/userfiles/files/desewesu.pdfIn PDF document text
    • https://ceccargiurgiu.ro/userfiles/file/mefewazofitenevu.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/8444489970.pdfIn PDF document text
    • http://retailcop.ca/files/89706458228.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/galurusitexaraxupamebuwo.pdfIn PDF document text
    • https://hahapediatric.com/uploads/files/202109200004081966.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=free+unlimited+instagram+followers+without+human+verificationPDF 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_off00012fb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000147cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147CF 11152 bytes
SHA-256: 2c2910ec7acbb1d107483cff565fb513086d898663a2da0ad6e1986219ab7f9e
font_02_sfnt_off00016184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16184 20132 bytes
SHA-256: cfdcea39816bd01a92f0974034e59d9a804755c0cc597debcb32993be28a496e