Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e90719e7b815d29…

MALICIOUS

PDF

68.8 KB Created: 2021-09-26 11:29:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 60f7d01a984396cca1194da0f276f0dc SHA-1: a2b2d2114e19d5854dfeb60ce58f855481d087b9 SHA-256: 8e90719e7b815d293d2e59dbc6fbd8e7a4015d656a7fdf937236f5efa4c8c60e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious. It contains numerous embedded URLs, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links, combined with the PDF's structure and the ClamAV detection, indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://smidgel.ru/uplcv?utm_term=introduction+to+fluid+mechanics+fox+7th+edition+pdf PDF link annotation
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b75533b6a5---gebolobatigixiwiralo.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/42190950262.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210916_2C9EB463DA79C3E2.pdfIn PDF document text
    • http://2sisaccount.com/userfiles/files/mutudanifusalijukowi.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///32954241003.pdfIn PDF document text
    • http://rklatex.com/userfiles/file/xakaduwada.pdfIn PDF document text
    • http://kuryakyn.ru/userfiles/file/79413107612.pdfIn PDF document text
    • https://fanaf.com/article_ressources/file/77702550543.pdfIn PDF document text
    • http://ahzycw.com/upload_fck/file/2021-9-23/20210923173736331019.pdfIn PDF document text
    • http://worshipedia.net/sites/default/files/file/wavopupakezikuj.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/xuxikiz.pdfIn PDF document text
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/wolapazadawirumep.pdfIn PDF document text
    • https://ssmahavidyalaya.org/lion/uploadedfiles/fck/files/file/85777310483.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210908_04812D7ED29C4042.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f64cc4a892---rojuxe.pdfIn PDF document text
    • https://hkfew.org.hk/ckfinder/userfiles/files/xokojo.pdfIn PDF document text
    • https://777mto.com/contents/files/13717751590.pdfIn PDF document text
    • http://xn--80aafbjcazdrhzgiddbbcsg4l.xn--p1ai/pict/file/4187195845.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b647da3687---60080854731.pdfIn PDF document text
    • http://wellgroup.cz/UserFiles/File/pufufopaviwadizolabonomet.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_off0000ae95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE95 14672 bytes
SHA-256: db4c1d6143917aa6cea0c5764b345c7821248522f25f20c110457a61820a7f10
font_01_sfnt_off0000d36a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD36A 11088 bytes
SHA-256: 4ae6092289d499c90d78d5a461d37432d9239067333a280aa93fdcf7503e956e
font_02_sfnt_off0000ed20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED20 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1