Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dd266bc8b275ce5…

MALICIOUS

PDF

92.5 KB Created: 2021-07-15 12:10:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 34997d0ab0dc4b236d6a7dd1be0aca3b SHA-1: 0d7976540f16dc4527e1c8c8dba735d7ed43c26d SHA-256: 4dd266bc8b275ce58a55d64d7b964af87e909459ff2ebee21208aa9f877222ce
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a link farm pointing to compromised WordPress upload directories, suggesting it's used to host or distribute further malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/7erqr100ou9luudeck7q1vi6m0/kaxedorovurom.pdf In PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16088e482739f5---88671042842.pdfIn PDF document text
    • http://sro52.ru/uploads/files/86860973254.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/gesuvenobasuro.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/3r2rpnelbcvt2cuie6smcgmoo4/89985562858.pdfIn PDF document text
    • http://uhy-th.com/image/upload/files/12462424571.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/38067107656.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/aed7e2f750e9c5e10eed194da275d635/35547738969.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/b47a70ce2f0b9ced222d0abba3c27e6e/tivitirup.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/a65ec34d869732384aef34543f7af5cc/nometipivowipatedi.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9c676e6d4---sojexokosuzokarol.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/6b478990d4e8bb0e34f71acf3f9dda31/jekotigavod.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/da848249ede7079855f1206359e774f5/9639637767.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3263bd509---2524988454.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/2ba42e7ebd4fd0d7b74e2a9d0b20c2b0/laxaladalukilone.pdfIn PDF document text
    • http://biosite.ru/images/news/file/31437752120.pdfIn PDF document text
    • http://fygl.net/uploads/file/280347431392.pdfIn PDF document text
    • http://cybernet.asia/UserFiles/File/tazimosuvimidalaletadavox.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097110e468a5---7344995053.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cccc053bdf---15039683444.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/24744264512.pdfIn PDF document text
    • http://deborahmayerlawoffices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jubezufivoxikanibom.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/16083689c4b88b---82466112652.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/12bnbl0e1ba48q2u8khq62mj96/tumotibuw.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb24d44d972---17544952256.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=offer+of+employment+acceptance+emailPDF 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_off000106c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C1 17320 bytes
SHA-256: 1b6d6b0b0c22ae2ad237e5edc295097721babc63c547f9178fb82a3b5984f13d
font_01_sfnt_off00013446.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13446 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014c5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C5D 10612 bytes
SHA-256: 860f51901fecaaf9ab934ed0246942abc71021effa79b75931e86c30b4642dd0