Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f770fa3ff338b57…

MALICIOUS

PDF

88.1 KB Created: 2021-08-12 02:41:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1233286b54e2b59f72c32b365d160ce5 SHA-1: 0af1240b15d68455fef1a7ff515c63af93c97601 SHA-256: 6f770fa3ff338b571ab2473ff825eb71731780f87162fcba1a37580c9423082e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. Heuristics indicate these are likely used to distribute phishing content or malware. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094dffede485---redefalivigaf.pdf In PDF document text
    • http://itfkarnataka.com/cvsprojects/SSK/Source/2.0.0/images/files/putekowojose.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f77e2c0f4b---22506120620.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/vodegamogetiva.pdfIn PDF document text
    • http://wmhsclassof1977.com/clients/34196/File/kujukazojakilapiwisotad.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ffaba4986---7016611613.pdfIn PDF document text
    • http://napiarsaigh.com/images/mefigozefal.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607618e558db1---16337110624.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/a538a04ee4fe972c4a8c5b7a68d3fab2/17143009807.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609188d1f0ddc---vobuwogezutajato.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160764124eb136---3146640931.pdfIn PDF document text
    • https://guapa2.com/admin/fck/file/65353284583.pdfIn PDF document text
    • https://fruzsiflame.hu/userfiles/file/28077117480.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/87490849732.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b675ae82cc3---balokenimilurum.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16093d442f396c---dumamaxa.pdfIn PDF document text
    • https://gretajensen.com/ckfinder/userfiles/files/wukofofone.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/37932514353.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/44530819502.pdfIn PDF document text
    • http://malifer.hu/upload/file/gukejetex.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2281abcf0---51161540069.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160fc6642185e4---wilufazobiximosom.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c887cdf2a76---43310666235.pdfIn PDF document text
    • http://feuerwehrobrigheim.de/upload/files/47249274226.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/16091b46c7be5f---95317115853.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=best+black+friday+deals+electronics+canadaPDF 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_off0000f317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF317 17580 bytes
SHA-256: eee9318804b34b26d5f2620723593ec6e64f9b22cb9dbac5b1890373ae5526ba
font_01_sfnt_off000120c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000138d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138D8 10868 bytes
SHA-256: 10686d4d1b5f48cdc7b552b373c1d4359fafe8f1d07ac9890d9483eec30cc460