Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1ce20d156876623…

MALICIOUS

PDF

81.9 KB Created: 2021-09-19 14:57:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c7346745256a38d78016a95524314bda SHA-1: 9824533bf8ac26ed71cb0e1394d22da772b7c9a2 SHA-256: a1ce20d156876623f5c02104874d2a72af47d1eecd53371e90340cb36acc9c68
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm used for phishing or distributing further payloads. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with common phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://www.cddfct.com/up_files/file/30023125860.pdf In PDF document text
    • http://riskhedgetech.com/uploaded/file/1442076918613300488f6c1.pdfIn PDF document text
    • http://tongkhomica.com/upload/files/51918208852.pdfIn PDF document text
    • http://flomojapan.com/upload/files/21736701185.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/todelopotorera.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/2s2gfd1hfn7qemb81kgepcn3u4/witotimemonidokiroka.pdfIn PDF document text
    • https://adurucui.com/ckfinder/files/teror.pdfIn PDF document text
    • http://suriyedostlukdernegi.org/image/files/vexafufin.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/22858912163.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/10430744866.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/o8njue0rc25jep0hfg3qv5jcb9/daladazuwegu.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/f58aeae8fae01e81236bc6ceffe0efb3/51133260085.pdfIn PDF document text
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/93292672742.pdfIn PDF document text
    • http://jolanyee.com/upload/files/202109021204226529.pdfIn PDF document text
    • http://www.papelerialapiceros.es/ckfinder/userfiles/files/43275419904.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210918_162123.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/lupogewumel.pdfIn PDF document text
    • https://mitrasuksesku.com/userfiles/file/kaposurewak.pdfIn PDF document text
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/61926282497.pdfIn PDF document text
    • http://alwaysshine.com/fileimage/file/502492639.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/sabajagafazasiseduto.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/xurogakokosazewux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=is+will+a+prepositionPDF 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_off0000de40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f652.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF652 17124 bytes
SHA-256: acc6c76844bbf56fc12c4a45e782891ba07b91222397fdacdb5fe8471eefcec5
font_02_sfnt_off000122a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122A4 10284 bytes
SHA-256: d45bfd76942eb05365c43974250d247962a681370c4a98042d669dfa1ba5cd62