Malicious PDF — malware analysis report

Static analysis result for SHA-256 255b1b42fc512d41…

MALICIOUS

PDF

80.7 KB Created: 2021-09-02 15:22:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a786c08f094b0ac24fdd11b7cf6a350f SHA-1: 7733344ffe7120ecb3bf86b419edd403f100d6a4 SHA-256: 255b1b42fc512d415906154eb7c54302b895a6582f4074b0c91bfabe3561afa4
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution lure. The embedded URLs are likely used to redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://kimhoatra.vn/upload/fckimagesfile/lokuxajimodu.pdf
    • http://albatrossmrn.com/konadnew/userfiles/file/rakeraletalisolixiputo.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2fb37194c---gejagulexun.pdf
    • http://csc0351.com/userfiles/file/20210724112632_fo4t4r.pdf
    • https://datawire.gr/files/files/bopasavotavireve.pdf
    • https://leganordavigliana.it/uploads/file/77907798028.pdf
    • https://edoxmarketing.com/wp-content/plugins/super-forms/uploads/php/files/tktuecla7f0kra1ff9b0i4fs5s/demaxikofevutos.pdf
    • http://alltimescare.com/attachment/files/zemoxunerixuni.pdf
    • http://bazis-expertiza.ru/ckfinder/core/connector/php/files/11182598930.pdf
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/t7c1dtl81g8mre1vihg6j31ad2/firuwot.pdf
    • http://heibldr.hu/FCKfeltoltott/file/35357081506.pdf
    • http://thesetnews.com/images/fckeditor/file/11805517944.pdf
    • http://childconnect.com/swi/fckfiles//file/93235981818.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/ca7c5d4a23483fcdce7ec764ffcbd622/73360013707.pdf
    • https://gertiesbloomers.com/kousumi/nulook/upload/fckimages/file/34365748137.pdf
    • https://arichaindia.com/userfiles/file/50260896620.pdf
    • http://msslink.ru/userfiles/files/53316913411.pdf
    • http://angelescare.com/userfiles/file/fopimipelazezenipuxot.pdf
    • https://investir-petroleo.pt/ckfinder/userfiles/files/wagepawinoxojabijuvidisag.pdf
    • https://childconcern.in/trila/userfiles/file/4828536082.pdf
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/322cd5e74bf150521955378f561082eb/buxalenerupi.pdf
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/77781899065.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=deductive+argument+examples+pdf
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/c3edfa9ac20e9d583725f64bc7050162/xutopilekakafosimerekubuj.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_off0000d5e6.bin
9468500ed20021544e41636acdca8383a790af1987e5d99017a86a6e8fe23351
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E6 11112 bytes
font_01_sfnt_off0000efa9.bin
667535ec3669bec1a1071f3baa6e0236b5626a3cdd6bfc6d448bc9ebf0e19a75
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA9 17644 bytes
font_02_sfnt_off00011d72.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D72 16792 bytes