Malicious PDF — malware analysis report

Static analysis result for SHA-256 55daa2ce16c92b85…

MALICIOUS

PDF

83.3 KB Created: 2021-09-09 17:03:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8df0e79ae83fb98d4cc8e2469ca9c974 SHA-1: 7a8af0715830eff91e77bf280e402a1fabdde735 SHA-256: 55daa2ce16c92b852e7efb06666d8a5c10f66675b0930d20b8e7201e4e008146
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://tsuiteru66.com/userfiles/file/gupuridafedi.pdf In PDF document text
    • https://www.mftelhas.com.br/adm/Editor/ckfinder/userfiles/files/54302661851.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/6573862592.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/93113207085.pdfIn PDF document text
    • http://servicedental.it/userfiles/files/17738648542.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/51413905265.pdfIn PDF document text
    • http://exima.kr/userData/board/file/doxidabuxasake.pdfIn PDF document text
    • http://ucg-eg.com/userfiles/file/86925281882.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1612f956279df0---bibofunaxotid.pdfIn PDF document text
    • https://homestayhoian.thamtuddt.com/uploads/image/files/rurikodekopemafuta.pdfIn PDF document text
    • https://clubsecurite.fr/webroot/upload/files/79849019893.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/17933728131.pdfIn PDF document text
    • http://xn--38-mlcqjbufcz6h.xn--p1ai/userfiles/file/vipududozib.pdfIn PDF document text
    • http://aylabawadi.ae/userfiles/file/76775884380.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161325d3d7fcec---70649366040.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/kosuposifuwuxifipa.pdfIn PDF document text
    • https://wrd13.com/force/file/61877390002.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/65187d21ce8728fcf1861771ecea3691/84247212763.pdfIn PDF document text
    • http://sochi-vitrazhi.ru/ckfinder/userfiles/files/75431989474.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/a15e92e6bafd011252254790108be7d4/sewivavoxigepepikixazunub.pdfIn PDF document text
    • https://www.sudoku-cool.com/ckfinder/userfiles/files/24475483001.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/63169680750.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/74661369938.pdfIn PDF document text
    • http://baltic-rt.ru/ckfinder/userfiles/files/32499610215.pdfIn PDF document text
    • https://rubenferro.com/userfiles/file/82464717304.pdfIn PDF document text
    • http://hotelbellevuepalermo.com/userfiles/files/vedojetuba.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=new+slots+2021+mod+apk+unlimited+moneyPDF 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_off0000dea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEA1 18096 bytes
SHA-256: 0100f3e41d1e82fe6d388fe3b525534e0ebd8d0d4d474604d0f3d234889d1f42
font_01_sfnt_off00010d13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001252a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1252A 11116 bytes
SHA-256: fd939f34970e0e1058b9da60ecde8c5c5095b1fb1fa24e6a222a23bc74b80bb3