Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac9b11ee43c1ad45…

MALICIOUS

PDF

83.5 KB Created: 2021-08-22 00:08:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6038231be628b413178b4cec5bc8c9b5 SHA-1: 9d4a1e8d70afa65104fead209c67a91c29b64298 SHA-256: ac9b11ee43c1ad451df62dfbef380b58b9ecc0e6dc17fe052793265d6f07bbc9
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised websites that host further PDF files. This suggests a phishing or malware distribution campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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 http://kimwendelldesign.com/ckfinder/userfiles/files/suragigulatunatudifakesig.pdf In PDF document text
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/70062798827.pdfIn PDF document text
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/f3a099bf0aa01f6d1bd6170ca2194d24/nigexodek.pdfIn PDF document text
    • https://www.latentoac.com/portal/wp-content/plugins/super-forms/uploads/php/files/pb3ijj4skcsunl8e4aoo9rojc7/35686992100.pdfIn PDF document text
    • http://chanhbon.vn/media/ftp/file/21849334557.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086ba1688890---32953623276.pdfIn PDF document text
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/mufidimuwurexutelije.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/49777819419.pdfIn PDF document text
    • http://abw10thstreetne.com/uploads/files/wixirirotaxafipipe.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/23403100525.pdfIn PDF document text
    • http://skylineidaho69.com/clients/c/c7/c7306e0a9cc1d421caefa9c307ca601f/File/xijizu.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/20040546968.pdfIn PDF document text
    • https://sanipacific.com/attachment/file/vuxumizusugetelinewowijul.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/baba001f54b070ded5b1285695b36769/26561786677.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/19ef1f9f9e140787262e991a010b1086/wukejizewagijizugo.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/32061571143.pdfIn PDF document text
    • http://jngf.cn/files/file/wutazuzepivekitiro.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/4b03484f7f3eb61f68846ad4e4f2486b/45412748121.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/sakub.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/2f0fdc674b77e021b1aef170757c240a/27264950582.pdfIn PDF document text
    • https://biovuspharma.net/userfiles/files/6718983633.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160ecb5d87cd8f---kaves.pdfIn PDF document text
    • http://satakantaresort.com/user_img/files/79924385317.pdfIn PDF document text
    • https://ahreco.com/uploads/news_file/mawinipowetitebujokejukuf.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160be6b7ca2abd---84006858473.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=gmat+official+guide+latest+edition+pdfPDF 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_off0000def0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF0 17608 bytes
SHA-256: 438e5770b745a7ab8bfcbd19850b4e6210cc580bff9d00dd495058157ebf6882
font_01_sfnt_off00010d82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012599.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12599 11004 bytes
SHA-256: 866f589f3b43de7c02d2660d730a26cb9b84ca4fc8797017f05edfc9109357b8