Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d4eacd63409d59e…

MALICIOUS

PDF

91.2 KB Created: 2021-09-06 06:18:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 8bc53986eed0ba6c9075731ed2138887 SHA-1: b897825b250eb3def884b7d9c64aa98c7fb8db80 SHA-256: 4d4eacd63409d59e153aef939e85224a8e463e5cd696b5894510005f77aa3e5b
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a ML classifier and ClamAV, indicating malicious intent. It contains a link farm pointing to numerous websites, some of which are hosted on compromised CMS uploads, suggesting a phishing or SEO poisoning campaign. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://walnutcreekguide.com/wysiwygfiles/file/mepikabovojunugenu.pdf In PDF document text
    • http://ucity69.com/clients/861769/File/4724192893.pdfIn PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/ljbqj04rjgdsi99178u4g8v228/bopujefimowif.pdfIn PDF document text
    • https://studiorampinelli.com/file/45470732485.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/2ba7f630308bf6ea0167be84380377e0/17814796186.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/bowup.pdfIn PDF document text
    • https://stka.gr/ckfinder/userfiles/files/nonog.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/85837584836.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c26e1a6332d---61019057108.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/01c6f33a54a0bec83b5f62c749a01db6/45838754188.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/jebudunazegiwusowazefet.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/60074310074.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/9e1d828da481588ff7ab20475e2a4b2a/xujalomojifisodubapufo.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a8cf8adb1---mubox.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/39475155630.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/45520513490.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1608b2a3b4109b---90969893533.pdfIn PDF document text
    • http://ehs1958.org/clients/73155/File/6216507969.pdfIn PDF document text
    • http://szwygs.com/upload/vilawojopunilexigawes.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/77328725521.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/5ead6b23ddc669f887982eb24df53032/zimurotejijud.pdfIn PDF document text
    • https://hocaukhudothithanhphogiaoluu.com/asset/site/files/suxajoxijejevojutuzetup.pdfIn PDF document text
    • http://didopack.com/files/nefegazo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=livros+de+liev+tolstoi+em+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_off0000fcb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCB9 10416 bytes
SHA-256: 573b3b5360cca0f437ad536f8cf24fcd067cae5f762d2081dbf3e48393410c0c
font_01_sfnt_off0001145b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1145B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C6D 20216 bytes
SHA-256: dd0530a09b085aa582dff04746c0026c2300e223654fb14d6bd26023765153a1