Malicious PDF — malware analysis report

Static analysis result for SHA-256 648b368ea6aa4eec…

MALICIOUS

PDF

75.8 KB Created: 2021-09-16 04:17:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ff7f4de1499e98a726093bb4ede488b9 SHA-1: cce4562f2fbe30c1f39b633b119353b1222b17e4 SHA-256: 648b368ea6aa4eec423d09c08004e84403044e885d726c36d05c84a9c7ee70ef
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, and the document body was unreadable binary data, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://media-get.com/userfiles/files/xeradotijuziton.pdf In PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/gesutoporavajaxo.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/95634676348.pdfIn PDF document text
    • http://alhegazgroup.com/userfiles/file/89424342227.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/h68c6gqm4hr8lvs8m1976k661i/55006839039.pdfIn PDF document text
    • http://www.octopus-quatuorvocal.com/ckfinder/userfiles/files/21725749915.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210913_AFC76F51BB70FA84.pdfIn PDF document text
    • https://rumusjitu.com/contents/files/56151636564.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/85198990227.pdfIn PDF document text
    • http://gursakaryahukuk.com/images/file/81937183353.pdfIn PDF document text
    • https://kanalprofi.at/UserFiles/file/wufolosefubu.pdfIn PDF document text
    • http://xn--9i1b14l32gg2dsybq3b.com/upload/fckeditor/file/tudanebe.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/67864942876.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/64948749593.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/mitaralatuxebakidesugupin.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/29479457210.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/99763754380.pdfIn PDF document text
    • https://vietnam-pump.com/userfiles/file/kukon.pdfIn PDF document text
    • https://vrrc.heart.net.tw/ckfinder/ckfiles/files/6519100780.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e79751e5f6---nolifelalixuniki.pdfIn PDF document text
    • http://littlepearlbooks.in/data/eimages/file/44031698626.pdfIn PDF document text
    • http://nghieuphong.com/upload/files/38418256630.pdfIn PDF document text
    • http://ptichile.cl/userfiles/file/difenarosanusumamiborari.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/ijka1s5gsfciitna8oah1dvt0a/rixukap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=justice+league+dark+apokolips+war+downloadPDF 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_off0000c1b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B3 17696 bytes
SHA-256: 748900a22075dfd9a676169cc90318491e46b736344e95db0b4a61728e65b528
font_01_sfnt_off0000efce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000107e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E5 10956 bytes
SHA-256: 4a271633610c89072692dcee95cce947a11064987b04229369329ba50259a14d