Malicious PDF — malware analysis report

Static analysis result for SHA-256 db8120805dd33d11…

MALICIOUS

PDF

82.8 KB Created: 2021-09-15 13:31:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a6d8dac0fd25cf2f362b19bb031a57fc SHA-1: 2ac53d894678dd2eed3b7b5c33c9b6df98b505a6 SHA-256: db8120805dd33d11104ba8c607a247d15a025d95cebcc894c6ac063c550440c6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to redirect users. The document body is heavily obfuscated and unreadable, suggesting it serves as a container for these malicious links rather than user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://glycocalyx.nl/userfiles/image/file/63139498671.pdf In PDF document text
    • http://eco-building.cz/UserFiles/File/57338721327.pdfIn PDF document text
    • https://projetovm.com/uploads/files/rosav.pdfIn PDF document text
    • https://alistairmills.com/ckfinder/userfiles/files/ronef.pdfIn PDF document text
    • http://bielle-srl.com/userfiles/files/45141160313.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1613f96ab18d95---neputenefifafusajedikotug.pdfIn PDF document text
    • https://rotitelor.com/contents/files/wuwifejamelobefafogovi.pdfIn PDF document text
    • https://behagi.eus/files/galeria/files/58475327102.pdfIn PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/90395727687.pdfIn PDF document text
    • https://indiantiffin4me.com/nbloom/fckuploads/file/noxawiwoxasoxu.pdfIn PDF document text
    • http://xn--42-jlclgg6a3e.xn--p1ai/userfiles/file/2182418794.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/30501628539.pdfIn PDF document text
    • https://claudiodituri.it/uploads/69872439897.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/evu7ne9v2b2psr8vap9hb14g9s/44241011880.pdfIn PDF document text
    • http://geraldinekilkelly.ie/poduvakomixavegup.pdfIn PDF document text
    • http://vstarmp.cn/upload/files/20210905_001606.pdfIn PDF document text
    • http://diagcorlifescience.com/attachment/file/21494969346.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/34598685369.pdfIn PDF document text
    • http://digifast.cz/userfiles/26545926799.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/zapegizebamajetosebawuj.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/ponagufu.pdfIn PDF document text
    • http://erdbau-rauch.at/16302494391.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613011aac0305---neleruwiviritosivuzivumez.pdfIn PDF document text
    • https://architektor.ru/uploads/file/12877405248.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=the+copper+gauntlet+read+online+freePDF 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_off0000de80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f692.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF692 17680 bytes
SHA-256: 6edc67f0d2bd74e1c3375624ca104a264ad5205efc8e50578f41cea856c21717
font_02_sfnt_off0001244c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1244C 10796 bytes
SHA-256: 5bf965a049e2f02656c98841059c7d1bd5e53597b51efd4d21901104d5f5bac7