Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5ac0a4a55c6db07…

MALICIOUS

PDF

85.0 KB Created: 2021-09-20 13:07:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: aad3fd7d707594ea239efe459c2add3a SHA-1: 3639b0ba691a5bdc4ca7920decbea704d20cf467 SHA-256: b5ac0a4a55c6db07400fa6cd893324d20c1b73a29722f2ddeacd9fe6ff4a15d3
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. The file's structure and URL patterns are consistent with a link farm designed to lure users to malicious content, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://tomas-music.com/contents/files/71168993990.pdf In PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/forani.pdfIn PDF document text
    • http://attlas.center/userfiles/file/76974839581.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210917011330.pdfIn PDF document text
    • http://tuhocxuatnhapkhau.com/uploads/ckfinder/files/xezenufavoperejegukin.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1614758eb90a42---13685987085.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109130238207164.pdfIn PDF document text
    • https://orderpoet.com/ckfinder/userfiles/files/bigov.pdfIn PDF document text
    • https://sibconsulting.com/contents/files/munifazo.pdfIn PDF document text
    • http://metabolit.ru/files/file/40658198785.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/zamizusigaxavorexorike.pdfIn PDF document text
    • http://moriefrusca.com/userfiles/files/gubokesowefuwufelum.pdfIn PDF document text
    • https://ags-car.60km.com/upload/files/1401207929.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/vawin.pdfIn PDF document text
    • https://bursaphotofest.org/uploads/files/60706548077.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/35803426026.pdfIn PDF document text
    • https://eobliecky.sk/userfiles/file/diloxon.pdfIn PDF document text
    • http://onestep-tokyo.com/userfiles/file/9436172714.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614218ca95748---86090233867.pdfIn PDF document text
    • http://fusen-es.info/yamituki-n/uploads/files/32268197670.pdfIn PDF document text
    • https://damsindia.org/admin/uploads/file/nabik.pdfIn PDF document text
    • https://cabsfromheathrow.com/userfiles/file/21031522342.pdfIn PDF document text
    • http://lt101shop.com/userfiles/files/lasezawagaki.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/44252313664.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/161311d48c783a---wokasajorozutagexol.pdfIn PDF document text
    • http://gpshardorawal.com/hemkunt/userfiles/file/8899999320.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=watch+teenage+mutant+ninja+turtles+out+of+the+shadows+online+freePDF 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_off0000e67b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fe8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE8D 17420 bytes
SHA-256: a2cac309006f0407e33dd1f356eaa1353515b0d11b00a67ba4cebb9d0d99ce61
font_02_sfnt_off00012b8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B8A 11232 bytes
SHA-256: 0fb7545e89cae6fa6d34e6093c64cd924ec43acca1dd2612045c9dbbf6dfaf74