Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f89a8569f476ee9…

MALICIOUS

PDF

71.8 KB Created: 2021-09-30 10:46:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2e219b72c705f5fdaae4c4da45faf25c SHA-1: be49d21819e73369ac4626e58a18a08e4173547d SHA-256: 3f89a8569f476ee92be91c1db606ea6e1d8b957ff1ad98f32525c1d900d4704d
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous external URIs and links pointing to compromised WordPress uploads and other domains, indicating a link farm designed to lure users to potentially malicious sites. The document body is heavily obfuscated, preventing analysis of its direct content, but the heuristic firings strongly suggest a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=story+based+games+for+android PDF link annotation
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/km80rj9fv66385o102kguku90l/43559900238.pdfIn PDF document text
    • http://dkyangmei.com/uploadfile/file/2021091709170073499.pdfIn PDF document text
    • http://machulski.com/public/file/pexew.pdfIn PDF document text
    • http://elektrostroy.kz/ckfinder/userfiles/files/wuvujufivawajigi.pdfIn PDF document text
    • https://kinizsibank.inweb.hu/_user/file/34106678660.pdfIn PDF document text
    • http://autoachtercamper.nl/userfiles/file/91484670168.pdfIn PDF document text
    • http://ambiance-cinema.fr/wp-content/plugins/super-forms/uploads/php/files/bf94306aed77dea4fe17d94a1e7b7f98/wibokokivoxinuzizuru.pdfIn PDF document text
    • https://atlantidegattico.it/file/22637740367.pdfIn PDF document text
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/wutasewularir.pdfIn PDF document text
    • http://architettosbaffo.com/userfiles/files/lowite.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/3cgnkb9ec1f24heo3s4mip1knv/bogeno.pdfIn PDF document text
    • http://karimeh.com/public/userfiles/file/velivuxozo.pdfIn PDF document text
    • http://spzpoz-zdunskawola.pl/upload/file/48023195464.pdfIn PDF document text
    • http://talleresjpg.es/img/file/pomubudav.pdfIn PDF document text
    • http://vattucongtrinh.com/userfiles/file/37159201540.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/5279c91295e37fe5147f8e25de606127/pevekeguruloge.pdfIn PDF document text
    • http://lpkgoodframeupvc.com/userfiles/files/1606009674.pdfIn PDF document text
    • http://apicn.net/upload/files/78832511599.pdfIn PDF document text
    • https://bientannamhuy.com/wp-content/uploads/files/mivotor.pdfIn PDF document text
    • http://bolt-go77.com/fckeditor/userfiles/file/muvibivubutalegafag.pdfIn PDF document text
    • http://att-na.com/upload/23361370403.pdfIn PDF document text
    • http://fialki.su/jawidurosakebajizumufubom.pdfIn PDF document text
    • https://tresonance.org/uploadfiles/42801288566.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/51796560893.pdfIn PDF document text
    • http://cisseo.net/userfiles/files/88087049827.pdfIn PDF document text
    • http://lmnn.ru/userfiles/file/lunusuzena.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_off0000b59f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB59F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cdb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDB1 16752 bytes
SHA-256: f4e446a20f1b720f2d6fc6b944d08f88108d23aa654931f1b245dee3c84ec835
font_02_sfnt_off0000f82a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF82A 10980 bytes
SHA-256: 37cd0a496bb1e55e37b2a1f0c5b7220028e4c3ab87d2831ad37874f2dac1d92f