Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f8b206ecff0bcf6…

MALICIOUS

PDF

88.5 KB Created: 2021-07-29 16:58:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 66c3b0434918db53dd9cc8b4d6200a22 SHA-1: d8c77d17b98bf798fc877eca71279f56bb033379 SHA-256: 1f8b206ecff0bcf676cd01a03b1fcce2c8f5bfd22107202f0eeeec60384d636c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a large number of embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and URL patterns indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://irlanc.ru/uplcv?utm_term=big+ideas+math+7th+grade+red+book+pdf PDF link annotation
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b9136dce303---velebudumitarixevu.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//raseroxilom.pdfIn PDF document text
    • http://maciejabramowicz.pl/upload/files/file/jagovevadibowufupu.pdfIn PDF document text
    • https://crpm.ch/ck/ckfinder/userfiles/files/lexemadekoluzowujelob.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/82321532375.pdfIn PDF document text
    • http://language-coach.pl/uploads/files/12639096962.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/22126408744.pdfIn PDF document text
    • http://irths.com/upload_files/files/60649621043.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bd81288b1a3---99797320232.pdfIn PDF document text
    • http://didopack.com/files/setapal.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/3beffd1346052f9bff224e4382927038/90759641744.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-6-26/20210626150810943986.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/d91103f3683caabb99edce3247a1cd71/52061910430.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/77728036263.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/78764285379.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/8a3956306f835489bf82a011a0539289/guramibuzukuzegik.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607057eaf060d---73574332893.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3b3a1b9178---sukapenamim.pdfIn PDF document text
    • http://aurora-c.jp/files/files/65635286270.pdfIn PDF document text
    • http://viprealestatebrokers.com/userfiles/files/dabiju.pdfIn PDF document text
    • http://deauville.ru/files/file/fupiligusima.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/kebakunani.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/58027664482.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/mdch6ommnl6ce0g3geca76ut6t/lonozejeze.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/7kql3c9et321vbiv87gd623njh/latetefa.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f098555d6---97052812867.pdfIn PDF document text
    • 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_off0000f576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF576 11128 bytes
SHA-256: 4d7d121a1bf385b71f3c167c9e012636a840f66422d0e77290a508b3568f4bab
font_01_sfnt_off00010f1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001272f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1272F 16968 bytes
SHA-256: d91ae8dd77f5283789e13e36dfe754f6a35d1a1be8ba988ae9c1a90a00c9420e