Malicious PDF — malware analysis report

Static analysis result for SHA-256 787ba3bd7f92bd5a…

MALICIOUS

PDF

69.7 KB Created: 2021-09-22 14:13:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6c1660b2256e3a24a215cc3d86dfce65 SHA-1: a7620b488251e5051dc29f5d48473e9b73f0f390 SHA-256: 787ba3bd7f92bd5afa1b6038bdcca1479d1458626b61af7c1bbcf92f0ebc0771
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple URLs extracted from the document point to compromised or disposable hosting, suggesting an attempt to distribute further malicious content or phish users. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://sgrappresentanze.eu/userfiles/files/25326480677.pdf In PDF document text
    • http://lnianemarzenie.pl/userfiles/file/regopepomatomukugetegok.pdfIn PDF document text
    • http://khachsanmyngoc.com/upload/files/xumojupive.pdfIn PDF document text
    • https://jnnjhansi.com/userfiles/file/jiwibeworivagokukurinuvan.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/11911176204.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/23127232102.pdfIn PDF document text
    • http://garant-fond.ru/ckeditor/ckfinder/userfiles/Images/files/60184568194.pdfIn PDF document text
    • http://ser-buk.com/userfiles/file/70665855046.pdfIn PDF document text
    • https://ietc-oman.saktoon.com/userfiles/files/finasesox.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147bb5550983---jowosopifufekovi.pdfIn PDF document text
    • https://timminsrenovations.ca/file/pwT4fOEh1uFrzgL4.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abd3a0779b---fibabuvotol.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/90772ba7a15cb5fada4190e3450b0fc9/99794559200.pdfIn PDF document text
    • http://obasekiestates.com/UserFiles/file/62726333054.pdfIn PDF document text
    • http://888chji.com/userfiles/files/97425997544.pdfIn PDF document text
    • https://gdwtechnology.com/fckeditor/file/In PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136a439528c7---novikakuziveneduvoxe.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/foribekatuwo.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/75540895752.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/kefusonerufutadega.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/qcqjarrs179qdiirls997nbvk1/rupazojiduboxawotineji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=usb+bt+joycenter+apkPDF 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_off0000af88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF88 10712 bytes
SHA-256: 54523ea4954b5da3d9ea69ff82d52d6d48338a69ad881ff2e67cd948394b30de
font_01_sfnt_off0000c830.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC830 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e042.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE042 16208 bytes
SHA-256: d0116392e2014156b5ec4c2d81e7e2a3435ad66e6daa7534be95f5f30f60248a