Malicious PDF — malware analysis report

Static analysis result for SHA-256 a655ddbc351fd5a4…

MALICIOUS

PDF

83.8 KB Created: 2021-08-09 03:05:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: cf0f37ad43e54eddd4a2058fdda23927 SHA-1: 727ae877e8ea11ecaa93f7b1894e033c2b9651d2 SHA-256: a655ddbc351fd5a4ff93179533bc83fb1461bfec1b76d2339581b076d95609ce
164 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites, suggesting a link farm designed to host malicious content or redirect users. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL findings are sufficient to infer a malicious workflow.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cab46446c7---85634945611.pdf In PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/ntj5fb6ss5lqqvb8itps70jaq4/vogizokiwigabikapuwog.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f5b70b958---43515308789.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/40032851637.pdfIn PDF document text
    • https://luminex.pl/upload/file/bolixepisikaf.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160863ed27e75d---dizosutumosefu.pdfIn PDF document text
    • http://skncn.com/u/files/daxanasijatotodojuv.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/dujotanuvetopotok.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/0fdb8fd3e9feb3337e58d27031bde9ea/dekitimeropekuxotujove.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084c1e3a610f---64144660912.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/944eecb7bff2991aba9b71ae448023f7/zerimisir.pdfIn PDF document text
    • http://erictex.com/ufiles/files/1272250032.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/mo8b61m3qiflll70bi13evds67/32835840781.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608cbd84de8d6---67742728436.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/290c12c8f00b6571fb1e25c84a1fc998/nigagisodupov.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/05bd9c3f1965b3adfa7235aad6a6a3d6/sesugetajofuvasoxapuleneg.pdfIn PDF document text
    • https://atpl.aero/ckfinder/userfiles/files/valawesoboret.pdfIn PDF document text
    • http://xecuoihuyhoang.com/uploads/userfiles/file/3564069096.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ac36544ce76---47809789713.pdfIn PDF document text
    • http://pechati-piter.ru/userfiles/file/10680844838.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/9v67lglnnpt161aafhvb4lof83/lujalorudoxegab.pdfIn PDF document text
    • http://minhanh.com/files/jenafase.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=is+silk+screen+printing+profitablePDF 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_off0000e363.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE363 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB75 16256 bytes
SHA-256: 3c1039788b9e7c74d7355f1e81e70a2d190ad3ac316d644a09a2733582ace227
font_02_sfnt_off00012588.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12588 10840 bytes
SHA-256: ebe632fc036632b1c7262ce2c2bb75c1619c9227fc0e8bbd26411a1acc2cdf44