Malicious PDF — malware analysis report

Static analysis result for SHA-256 4685c445b7fca720…

MALICIOUS

PDF

70.6 KB Created: 2021-08-20 15:06:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 29633c4472cba1dc5df01f82a4520364 SHA-1: 987d21b0bc616cb9ac64d5dc44e326323268cc51 SHA-256: 4685c445b7fca720304eef3bdab5411c72f27ff41123ff17a75bb5e70fd4c44f
154 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 websites or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of external URI heuristics and link farm indicators reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8935

Heuristics 5

  • 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
  • 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://bursac.net/userfiles/file/683964609.pdf In PDF document text
    • http://air-con.ru/upload/files/41295139396.pdfIn PDF document text
    • http://uceng.net/_UploadFile/Images/file/13636275437.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/wokoxalatina.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/fe39fdf0fc398544acf0ddb6ba1df20a/zomalosa.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/31843437820.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/40401564512.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/0bttc931tgjn829ronjlstcedj/19432131622.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/5t3ds53jkgkt457falrvmiu9h1/10693040678.pdfIn PDF document text
    • http://kleiberit.ru/files/file/13089040310.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160864786ca648---konitupomap.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3ecfaa3596---30118418171.pdfIn PDF document text
    • https://ezastupitelstvo.sk/editor_uploads/system/files/kefasevamukirodofifizofi.pdfIn PDF document text
    • http://abwpetersburg.com/uploads/files/2430415518.pdfIn PDF document text
    • http://suapaiatuipelehakefamily.com/clients/80707/File/xiraxuperojalibijadeb.pdfIn PDF document text
    • http://deckdreams.ca/clients/3/34/34055ef41782f8f15ebf372c1e39ecad/File/vedamurozelifapugimetut.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0cd3de227c---98397554170.pdfIn PDF document text
    • http://suseefinance.com/userfiles/file/kamogo.pdfIn PDF document text
    • http://beveragesgs.com/userfiles/file/fijoxibamitozajowudineso.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606efbb7d6d3a---tavalifikujogetasovi.pdfIn PDF document text
    • http://ekotronic.eu/files/file/9816908833.pdfIn PDF document text
    • http://ergo-logo-bamberg.de/userfiles/file/96457238694.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9dc0e2dd29---wepovobolulatu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=incident+investigation+report+format+in+wordPDF link annotation
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC89 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f49b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF49B 16828 bytes
SHA-256: 594e27d4d08c391184949e9bbd62c158b3b10e2148498c3cb75c1fdc7cad53ff