Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ca86bdfd74231aa…

MALICIOUS

PDF

81.7 KB Created: 2021-09-01 22:24:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 775255a648f90b451500eb4f71025469 SHA-1: 7ed764b1ebbb6a726c209e8bdb47a92768afb9e6 SHA-256: 8ca86bdfd74231aac046c70f12ebd72001f008121f5f8fca6f239df11aef2c07
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://drafthe.ru/uplcv?utm_term=pdf+display+in+html PDF link annotation
    • http://guides2alpes.fr/uploads/file/3968777536.pdfIn PDF document text
    • https://carparts-fixture.com/file/file/xapizop.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094644435d8c---76623237972.pdfIn PDF document text
    • http://fzcce.com/aimgs/uload/files/33943248500.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/421568e7432f9604f453f24fd7dbbbcc/vidoj.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/sesetakinotofimogolu.pdfIn PDF document text
    • http://chinazzjx.com/d/files/tavejinosotejomuleku.pdfIn PDF document text
    • http://caphegiabao.com/upload/fck/file/1892593574.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/wotepumijifitulosivol.pdfIn PDF document text
    • http://cokhibaosang.com/media/ftp/file/rewetodo.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a98da788a9---potomabopena.pdfIn PDF document text
    • http://www.sloepverhuur-debiesbosch.nl/upload/files/nekobovituvofexif.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/24033788723.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160970daab9019---gimaduwiluzejeda.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160aa5a6e31916---7693140340.pdfIn PDF document text
    • https://kaptenhoki.com/contents//files/52723833358.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/58111737215.pdfIn PDF document text
    • https://menu2uplus.com/images/file/69040464791.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/2nrqcn0vp31hhd02krapgc4hri/33647871327.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160924fbc907bb---wimibafamurusiwen.pdfIn PDF document text
    • http://reutlinger.pl/userfiles/file/zimubufus.pdfIn PDF document text
    • http://pritchardreunion.com/clients/81409/File/30493964853.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_off0000d895.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD895 18412 bytes
SHA-256: 79507c2b9495cf43646c2ea436d0f72561b5a5ee3bbf33a6244424855609a921
font_01_sfnt_off000108be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108BE 10524 bytes
SHA-256: d7d4e29cd49e4acee21abbaf4c579d093e888d7932588c61e1bd69742cf97cfd
font_02_sfnt_off00012078.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12078 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1