Malicious PDF — malware analysis report

Static analysis result for SHA-256 b75b3ae705cf40c5…

MALICIOUS

PDF

85.7 KB Created: 2021-09-01 21:45:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 329d86474f7b376953b48a507291eb82 SHA-1: b7ce78176aaaed340a91fb9ecb12567352231da6 SHA-256: b75b3ae705cf40c597fa477369540262a0a855de27dd4153da733ec9a3daa39e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to assess its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/ceac446dfa1482146dc0a60fdad4b4fe/98107308507.pdf In PDF document text
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/popesifiz.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d29ed1500---munog.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612cbaf08de5a---69594630364.pdfIn PDF document text
    • http://www.nomorcantikjoss.com/file/xuvenalosokume.pdfIn PDF document text
    • http://hanmih.com/userfiles/file/20210721084941.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1627927779.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1608291c2d63a3---nofewezanakedowa.pdfIn PDF document text
    • http://ogcdc.org/uploads/ck_upload/files/67095372524.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/8317912077.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/059dea9968a4444b3ac598fffac70494/gedaxuwujibujux.pdfIn PDF document text
    • http://elitvorota.ru/f/file/75607444310.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/2bll7uc5evvnqhlgdm37pjvvfi/12514668771.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/44751539607.pdfIn PDF document text
    • http://celiapopememorial.com/clients/4/45/45605e685ba8a3b32f56966823665796/File/1072501019.pdfIn PDF document text
    • http://nitexprofi.cz/userfiles/file/10239457604.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161042665a2337---6768012166.pdfIn PDF document text
    • https://loctra.net/userfiles/file/91742588325.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/t44s2aekrq3urcpm5q23ftlfj4/49384077578.pdfIn PDF document text
    • http://showplus.ae/userfiles/files/bobefebapuwoxidapuworofet.pdfIn PDF document text
    • https://karlholmbygg.se/UserFiles/files/zunifajobalazomomi.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612197ed8548d---15146156354.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=tab+theophylline+usesPDF 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_off0000e741.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE741 19352 bytes
SHA-256: 91f28c7a4b42d910d29e89bb6035987b64a3509fa0ae84dfa4bf2a5b5ddd2ca7
font_01_sfnt_off0001186e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1186E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13085 10568 bytes
SHA-256: 4e7ea949c227515a811e332bf97e70c802544e344084f7d6affb654d35e00534