Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7e9d358b2a360b3…

MALICIOUS

PDF

81.9 KB Created: 2021-06-23 11:09:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 7ab22b2d597be19b19d9ec75e1a626dd SHA-1: a687f6c70fd72bc52156aa7af938a2ced97f8294 SHA-256: e7e9d358b2a360b3e1b88742ec09fe93d7185ba6076c08d7eb9d7844a586e08f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. It contains numerous links to external websites, many hosted on compromised CMS uploads or disposable domains, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, contains references to interview questions, likely a pretext to direct users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/d57ekktkgj3hcmfmq2p8uuln1u/9736726565.pdf In PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608a02d4190a4---22246016829.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/81956343383.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/omhlo9j5jbhuisibv8c6f245kj/bumuririkosejebek.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afd3828b674---gekusoneme.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/34165652871.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608265a173519---makumesaj.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/wiloxulopu.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/hsjqajn6uo687h3kou9el2g9q2/kodaxukezu.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160867bf622626---33068502306.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/5c0b98bb3984ab993e893d34b59944c1/vimedikavimekibisagesizi.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/2e193e098f23017ed14c8754fe108145/fabolixugezifun.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/topujufigexefimowu.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/8vtv5ib9g0vcgcqtn29l38i2om/juzudalamulaxarabopaxefo.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/6bee7389763de56fd41d149dfce817a1/zivaxigekaxuno.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086d7098e117---mijugado.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/56338221443.pdfIn PDF document text
    • http://firanywiktoria.pl/uploads/editor/file/10950273037.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb84f7b9993---3718783975.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=behavioural+interview+questions+and+answersPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000101cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101CF 5240 bytes
SHA-256: a94de3f0f146b04507d8d2c0a5933cb62667708c3d08f3cc5ac59f154599e2c0
font_01_sfnt_off000113ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113AD 11444 bytes
SHA-256: d95489ca82a18e4a26611010ebc1437317d3ac91dd7c34447118148f407b7eef