Malicious PDF — malware analysis report

Static analysis result for SHA-256 3afcbc3dc7772465…

MALICIOUS

PDF

74.9 KB Created: 2021-09-07 18:28:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ade3c03260cf76e6a2dda602cf3d10e0 SHA-1: 476374e18ef8be8b69c426ed255d90112b40b7d8 SHA-256: 3afcbc3dc777246511da9f2ce6db6019cd6b5c62d75baee3c43ded1731565f2c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm utilizing compromised CMS uploads and disposable hosting, with numerous embedded URLs pointing to these sites. The document body is heavily obfuscated and unreadable, suggesting it serves primarily as a container for malicious links rather than user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://lauraestetica.com/userfiles/files/defemadivopoxubuwepafix.pdf In PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/636f4099859f42e617dae247ac820814/wefopakes.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7847a84a3c---3209199391.pdfIn PDF document text
    • https://hotelindigha.com/FCKeditor/file/lotimexekatiwixiba.pdfIn PDF document text
    • http://angelofthewinds.org/ckfinder/userfiles/files/86039205448.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/7cvhfkj0kkri19dknkr84lae00/kenaxusamajenasefewexi.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/a60ba6cbf282e5e5db877b71f6eff74b/33003853346.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/d17129f3d7c54ed5858fa9dc2c4fe150/48493893820.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/basosu.pdfIn PDF document text
    • http://gillsandgeckos.com/userfiles/file/51065376285.pdfIn PDF document text
    • https://www.sudburyhighspeedinternet.ca/wp-content/plugins/super-forms/uploads/php/files/301aee2f4c2f5ae339091b27ae4c37a9/tijako.pdfIn PDF document text
    • http://dfwarbitrator.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zuwafadegugovov.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/36804058293.pdfIn PDF document text
    • http://mamaskitchenorder.com/uploads/files/lofurowe.pdfIn PDF document text
    • http://feriaalainversa.com/uploaded/files/51694586184.pdfIn PDF document text
    • http://donahoelawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tiruvikafemovutaxe.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/tuvub.pdfIn PDF document text
    • http://nowyhotelik.pl/userfiles/file/74283881243.pdfIn PDF document text
    • http://gerastar.com/userfiles/file/gitogokoketid.pdfIn PDF document text
    • http://tnslib.net/userfiles/files/5059406057.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/bodixisugijezatimalok.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/5890048576.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160817c38b799d---87112310535.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=bleeding+time+duke+method+pdfPDF 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_off0000c30c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC30C 16508 bytes
SHA-256: a86452537486a0ebb67918155f9240fb589abc01cb4fc74c45aa06aeaf12441b
font_01_sfnt_off0000ed7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10593 10760 bytes
SHA-256: 2af55d32a40ec69404708ef78d5d6b03a610712a23d65c83d6a7c2693b8db3e9