Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb136bc816e7ac6f…

MALICIOUS

PDF

82.8 KB Created: 2021-09-02 08:23:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ae556deb6ad05ad5846fb23c5f2bb6cc SHA-1: 28c1177f3e2803051b6780e109ad606f2bd86149 SHA-256: fb136bc816e7ac6f221b21f61e397dd4ecc51e43854a57f78b7eede50547bd45
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, so the primary attack vector appears to be the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://clear-es.net/yamituki-n/uploads/files/loninoxifad.pdf In PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082e3a6f1fd7---7717721496.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/51377075867.pdfIn PDF document text
    • http://tunglamgarden.com/images/fck/file/xatibalex.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/bapikabikonisazu.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/d5ba27009866940bb70028c712b27c90/wurokov.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ac11e7d2a65---23480263626.pdfIn PDF document text
    • https://kocarbonag.com/luutru/files/zemubojogokedologeninidun.pdfIn PDF document text
    • http://mxagproducts.com/upload/browse/file/xajonogakefeligamor.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/65713138041.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/8003f31dff9bf3764bfc835a29e4edcb/wudutatigeli.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/magepax.pdfIn PDF document text
    • http://edgecs.net/documents/87037159618.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5ee12ee43---jesajetalibimemebejuta.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/nusisiserep.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/h82eeovlpjg8bm2homottqq251/nawubibazojipitugiga.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021072513082761.pdfIn PDF document text
    • http://nenkin-t.com/upload_img/ck/files/37421524639.pdfIn PDF document text
    • http://1night2day.com/UserFiles/file/36969284641.pdfIn PDF document text
    • http://koszyczarek.pl/userfiles/file/xiposewoxinorezerumazes.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/2b8b9be9080b8053e3bb446740660bd2/zulilusapupafanoneb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=bumble+bees+in+winterPDF 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_off0000e249.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE249 10368 bytes
SHA-256: 03bafcce2d078d73f2782073c4cad9e48ce47c55fbaa8ffcd733ce73853f0bcb
font_01_sfnt_off0000f9bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BB 16796 bytes
SHA-256: ae38f0ecf296423a98bb12de8536a6589ebb3f60f2266b77052b77d60be7fe9a
font_02_sfnt_off00012549.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12549 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1