Malicious PDF — malware analysis report

Static analysis result for SHA-256 878f5cd4dc3d41ae…

MALICIOUS

PDF

69.0 KB Created: 2021-09-27 22:27:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7e3c6af9f0e7c1b50a0602044954beaf SHA-1: aef24bdf3699e3f84d618b708c0a7e9e9f89e67b SHA-256: 878f5cd4dc3d41ae6436c491bd5916e253e5ad1b3c0339dfa5af69e651625aaa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious redirection tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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=pokemon+trainer+canyon+apk
    • http://gniortho.com/files/Upload/file/doxebujotobixofajoxoxote.pdf
    • http://webinaris.net/ckfinder/userfiles/publics/files/ziniwaxivanuxowajizekulow.pdf
    • https://guptajimarriagebureau.com/userfiles/file/30448267276.pdf
    • http://mobilahomedesign.com/userfiles/files/54529088164.pdf
    • https://eirai.org/editor/ckfinder/userfiles/files/34056528714.pdf
    • http://www.kroonzuivel.nl/ckfinder/userfiles/files/xogewujimufosoj.pdf
    • https://jasz-pap.hu/UserFiles/file/xutejesesil.pdf
    • http://shimamura-mail-order.com/userfiles/file/soxobexebol.pdf
    • http://kurier48.pl/files/userfiles/file/zuxopabopejafi.pdf
    • http://le-nora.com/userfiles/file/tifukarirusef.pdf
    • https://turystycznapodkowa.pl/userfiles/file/47983920038.pdf
    • http://webs123.com/userfiles/file/2375064814.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614029187057c---wanixamuwitajikedovudeb.pdf
    • http://a-swiss.com/upload/userfiles/file/gijuna.pdf
    • http://kimhoatra.com/upload/fckimagesfile/jedutelowakogegaruramog.pdf
    • https://www.tristar-technology.com/ckfinder/userfiles/files/magovefazigupevifilow.pdf
    • https://bc2000.order-pro.com/ckfinder/userfiles/files/60003878768.pdf
    • https://butagallery.com/userfiles/files/64043398215.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/9d1e7279ca7b1b3bae14b324eb3a19e9/vimemejujumobodegudota.pdf
    • http://uptownchantilly.com/uploads/files/39151798170.pdf
    • http://dulichtantai.com/files/uploaded/files/vogezibag.pdf
    • https://gres-k.cat/userfiles/file/dofapegalotodi.pdf
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/7b6bd63201ea9ce811bd765e1ae50a25/56542242194.pdf
    • https://mkserwis.pl/userfiles/file/jegat.pdf
    • http://formpart.com/upload/ckfinder/files/61027591659.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b010.bin
2270b52362adf756919b5827d90406dfffbe700d461aeff2a98f7383e4874fa1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB010 10528 bytes
font_01_sfnt_off0000c812.bin
5411907cbebcbbb8f25ea210add38fabf77f4677f706c332988c653594612d94
pdf-font-stream PDF embedded font (sfnt) at offset 0xC812 15264 bytes
font_02_sfnt_off0000ee84.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE84 16792 bytes