Malicious PDF — malware analysis report

Static analysis result for SHA-256 d45c8df9070f29da…

MALICIOUS

PDF

69.8 KB Created: 2021-09-28 04:47:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3fb84225ddf860473395aae58ae4f36c SHA-1: ad19f67339c6964ac7c4d51dcb8dfc4d03874177 SHA-256: d45c8df9070f29dae5bc6e99ce2434af36bb1670a55a58dcb1d7b701384ebc5c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It functions as a link farm, with numerous embedded URLs pointing to compromised CMS uploads and disposable hosting, likely to obscure the ultimate destination and evade detection. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect the user to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/294357c265f48487348ae3c680688942/46152957522.pdf In PDF document text
    • http://metallpress.info/files/34425094560.pdfIn PDF document text
    • http://ducnhua.com/upload/files/93101132570.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa7fbc85c7---5889580204.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/40875123618.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161501db59fd22---59827868060.pdfIn PDF document text
    • http://xinyaoqiye.com/upload_fck/file/2021-9-8/20210908125105159897.pdfIn PDF document text
    • http://studiozoppini.com/userfiles/files/powibisokumugojud.pdfIn PDF document text
    • https://s-oil.hoakhanh.vn/uploads/image/files/14307295883.pdfIn PDF document text
    • http://mfcpavpos.ru/file/62947640957.pdfIn PDF document text
    • https://dm288.com/slicice/file/xinowatenise.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/38475ad2eede55f8a6f1a946db085733/25256207119.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/muwalumakinulawiz.pdfIn PDF document text
    • http://xn----7sbabaajmdfbk3ddf3azka3b6a2r.xn--p1ai/ckfinder/userfiles/files/libabumunilebimij.pdfIn PDF document text
    • http://studiovalecchi.it/userfiles/files/54343537305.pdfIn PDF document text
    • https://huuphongplastic.vn/uploads/images/files/10317567738.pdfIn PDF document text
    • https://rumahbaruku.com/contents/files/62206759503.pdfIn PDF document text
    • https://phuquiland.com/upload/files/79974668033.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/34139033665.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/35320495998.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/gafawirebixarapedudaj.pdfIn PDF document text
    • http://bright-inter.com/file_media/file_image/file/sumujubevubumejiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=gta+v+in+gta+saPDF 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://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_off0000b11d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB11D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c933.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC933 9992 bytes
SHA-256: ced01e195dfd3d2c098f2734c0710190f54ad55341f9ccc90a400bbb35b3cef8
font_02_sfnt_off0000df81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF81 16488 bytes
SHA-256: 1d447163db8d3b7c1767ca86050e39ba74de5712a28a24b2d4ce72871b5bf923