Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4a8abf3f3b9c6b1…

MALICIOUS

PDF

73.5 KB Created: 2021-10-01 00:32:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 23c0f3e6983d1c5064818d822d5d0e01 SHA-1: b6954a95df90319f407d0abf243693d1e026562e SHA-256: c4a8abf3f3b9c6b1b45c7f724ff8fbbb9dfb4ec118b80eca82836b7ef9661355
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, with numerous URLs pointing to compromised websites hosting further PDF files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, suggesting an attempt to obscure the ultimate malicious destination. While no scripts were explicitly extracted, the nature of the PDF and the embedded URLs strongly suggest an intent to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://irlanc.ru/uplcv?utm_term=how+to+debug+android+emulator+in+chrome
    • http://klaaswester.nl/img/file/vesogi.pdf
    • http://yournamebadges.com/withyourdog/cms_uploads/file/paniwemeviwanipiman.pdf
    • https://transdeliveris.lt/userfiles/file/77724776583.pdf
    • http://tantex.org/tantex/tantexuserfiles/file/1021373546.pdf
    • http://daiichilogistics.com/uploads/news_file/69403385323.pdf
    • https://patoman.ro/ckfinder/userfiles/files/mukupadubuto.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16138441173609---3595020271.pdf
    • http://bhhangkhong.com/upload/images/files/xebogexowuzetajovuxozeja.pdf
    • https://digireg.dk/upload/77491813867.pdf
    • http://kochamsushi.pl/UserFiles/file/fajufizuvobuzadivitivebex.pdf
    • http://www.rify.us/cms-uploads/files/donujiditiduganus.pdf
    • http://dichvubaove.online/upload/files/43826149835.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e446602995---ruvupaburivot.pdf
    • http://waycreon.net/bhaskar/yii/upload/files/roxorax.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16140aa26c9c01---dosapepawokalumo.pdf
    • https://castel.ro/userfiles/file/75992881178.pdf
    • http://retailcop.ca/files/nufejer.pdf
    • http://mxag.com/upload/browse/file/sukinuk.pdf
    • http://www.coverseg.com/uploads/ckfinder/files/99175595181.pdf
    • https://dukra.sk/editor_uploads/files/mowujudunofenewesuwarifad.pdf
    • https://perfecthospital.org/FCKeditor/file/69362346605.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b52e.bin
db29e598b95c65b18e883ccf53304e1d5151331b7932016f237b53baf57e563e		 pdf-font-stream PDF embedded font (sfnt) at offset 0xB52E 10964 bytes
font_01_sfnt_off0000ce29.bin
d282c140ae57afe25d666650085dd339e6122fec1096c8ccf5beda9223c91e6a		 pdf-font-stream PDF embedded font (sfnt) at offset 0xCE29 18596 bytes
font_02_sfnt_off0000fe5d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5D 16792 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.