Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff2255df3ed2ebbc…

MALICIOUS

PDF

78.5 KB Created: 2021-09-08 09:28:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e8ea7a1e06c3afa9b7cc7fd0d9eefa04 SHA-1: b6e65798d8ebdc65add9a298139b543a08c8968a SHA-256: ff2255df3ed2ebbcb5ae0c671fb02c679371c44c243185974014f5a18c0e98e7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the presence of multiple suspicious URLs and the PDF structure itself point towards an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://catamma.ru/uplcv?utm_term=grade+12+economics+textbook+pdf+ethiopia PDF link annotation
    • https://detskeihriska.eu/ckfinder/userfiles/files/wisemujosazabureg.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/46481803515.pdfIn PDF document text
    • https://securitydm.net/slicice/file/rosuredexodefixoresiroj.pdfIn PDF document text
    • http://viettranslators.com/webroot/img/files/lekovijifibozamatasi.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/65848180226.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160b5363918047---18679056326.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/e814b3uqjnr4il2cbrven41ev5/76758539026.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/44286411395.pdfIn PDF document text
    • http://koreabulk.net/userData/board/file/33420067048.pdfIn PDF document text
    • https://baglab.pl/galeria/file/99391635447.pdfIn PDF document text
    • http://xn--zb0by3yusal20ak5lcidnwigi.com/ckfinder/userfiles/files/1627307623.pdfIn PDF document text
    • http://www.moyekolodin.com/files/xamitabatubofulaza.pdfIn PDF document text
    • https://samarpanbharat.org/trila/userfiles/file/36751418309.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/3nnnl76co1ivqq6dakitnuls73/xadobudo.pdfIn PDF document text
    • http://2990592.ru/ckfinder/userfiles/files/zurozowujamogizo.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/92154031633.pdfIn PDF document text
    • https://ecoretras.com/file/juwafo.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021090315481880.pdfIn PDF document text
    • https://flyingfish-stay.com/userfiles/file/sugonebozexijitamixut.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90ab474e0---wupedulexepebetafaj.pdfIn PDF document text
    • http://claudiamelchior.it/images/file/30542619127.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_off0000cd37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD37 11384 bytes
SHA-256: 959c20844ed4320686387839d8fc455ac0ec0744fca92cd4c7fa9806749b5d53
font_01_sfnt_off0000e7c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C1 17216 bytes
SHA-256: df8f01ae7723a09fa187ba0c9355eed0ccf13d9c0199bf8cbb395273709f9ae7
font_02_sfnt_off0001146c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1146C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1