Malicious PDF — malware analysis report

Static analysis result for SHA-256 7772a09ff9f9153c…

MALICIOUS

PDF

77.5 KB Created: 2021-09-05 23:22:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 85a52e04f4ac42b4070bf1a5dd901b26 SHA-1: e839c982a7c199852b5f2071614d89dda30092d8 SHA-256: 7772a09ff9f9153c7eb77c29cf27fd26699d74bba1308564454b284455a90555
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, directing users to potentially malicious or phishing websites. Heuristics indicate the PDF is designed as a link farm on disposable hosting and points to compromised CMS upload storage. ClamAV detection and ML classification strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://nomylo.ru/uplcv?utm_term=handwriting+worksheets+adults PDF link annotation
    • http://hanstime.com/userData/board/file/20434932574.pdfIn PDF document text
    • http://miroslaws.com/ckfinder/userfiles/files/71350347272.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/91949902787.pdfIn PDF document text
    • https://eitmedu.in/ckfinder/userfiles/files/2558172732.pdfIn PDF document text
    • http://polipack.ru/content/file/wobutezovejedetidepomel.pdfIn PDF document text
    • http://614move.com/clients/4890/File/80458537882.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/sb61qc0lqmpibu97ugru9srffb/mipil.pdfIn PDF document text
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/52534335835.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ced7324afc---66256625644.pdfIn PDF document text
    • http://nguoigiupviec99.com/webroot/img/files/31350796062.pdfIn PDF document text
    • https://www.lashharmony.co.uk/wp-content/plugins/super-forms/uploads/php/files/jtt4nrbl48edujfslj1kcf6oaa/gefevexozuzaperez.pdfIn PDF document text
    • https://euroialinsol.ro/userfiles/file/manifipezubapajivofananaz.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a019a5a3fc---17658929169.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c43d657d47---75203993107.pdfIn PDF document text
    • http://www.romanschatztruhe.de/img/files/27753861640.pdfIn PDF document text
    • http://easttbirds88.com/clients/d/d7/d767393c090093bf18db16876c07b5c3/File/70135672161.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2563ba821---6311831654.pdfIn PDF document text
    • http://uat2.hkha.com.hk/ckfinder/userfiles/files/pelesaguxiwegipez.pdfIn PDF document text
    • http://grotech.in/userfiles/file/vonixalejuduvad.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/48490155472.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_off0000cb6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB6B 17356 bytes
SHA-256: 1c82141086a4d606ad618dcb17834251ed2e92100ebd0225be453978012161e0
font_01_sfnt_off0000f822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF822 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11039 10796 bytes
SHA-256: b7a26d9e5f1b938b33de39864f3e4c4e661abfcf1a230b4ff039a5f325f8f455