Malicious PDF — malware analysis report

Static analysis result for SHA-256 66aff5d9903cc07e…

MALICIOUS

PDF

176.0 KB Created: 2021-10-08 20:10:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 24f4e555703756714d61abffe9bded34 SHA-1: 11ed2a0a64511672bd7f9f0e10db1ed5812175ac SHA-256: 66aff5d9903cc07e6855effebb28654e7a56edd01c677371cce2fb58b39cc706
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to numerous domains, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URLs suggest a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://inwebjor.ru/uplcv?utm_term=local+government+act+2013 PDF link annotation
    • https://unchiulmihai.ro/files/fckeditor/file/zaxijibupolovo.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/25540261698.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/14849280724.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16137308f7ad4a---wavagizaxuji.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/60904937435.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/2027475001.pdfIn PDF document text
    • http://szwygs.com/upload/riganiboj.pdfIn PDF document text
    • http://pololanna.com/user_img/files/28800752829.pdfIn PDF document text
    • http://medi-sen.com/files/files/tunuzidotirifig.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/pejopezipom.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/10077036404.pdfIn PDF document text
    • http://www.facyt.com.ar/ckfinder/userfiles/files/33948061350.pdfIn PDF document text
    • http://bodemveenweiden.nl/bodem-veenweiden-img/rivezulawit.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1615f7e0f75e98---47691439407.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/96038930096.pdfIn PDF document text
    • http://auto-rad.pl/userfiles/file/zuketumanediriretabu.pdfIn PDF document text
    • http://rvhifi.cz/files/file/dubepufotuloso.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16153968488c3c---jumibepikodomazamola.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/lamabi.pdfIn PDF document text
    • http://internet-trade.cz/UserFiles/file/fubuwagomijajukako.pdfIn PDF document text
    • http://bilafafafa.com/shopadmin/upload/files/14169477072.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16132154882fce---19424330049.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_off00024a4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24A4C 10804 bytes
SHA-256: bb3b8fa5bc83f68526c1976e3745ba07cfaf19907778b5f5f306f9fc35bbf099
font_01_sfnt_off0002635b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2635B 21604 bytes
SHA-256: 7de33da87a081770ad5481d48d8f7e78eb6f5001f296432a2b42f1ae558188bb
font_02_sfnt_off00029a24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x29A24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1