Malicious PDF — malware analysis report

Static analysis result for SHA-256 61033f185e0bd57a…

MALICIOUS

PDF

93.6 KB Created: 2021-07-09 01:54:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: f53c88672dac05038879c8cd4df927a7 SHA-1: 3848f98f1cc5fa7312a7a6c874dd7defd1f24586 SHA-256: 61033f185e0bd57a7d22c8c0ab1529847bf2e82f093231dcca3cfb3567e6e846
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple compromised WordPress sites, likely intended to host malicious content or redirect users to phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing trojan. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not meant for direct user consumption but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/bbc6628cfe7320cfb65a28f8d1512042/95813706690.pdf In PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/3dbdeb882ee8180ac7cc12ace598a673/4724224707.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2049850a0---mixokalamisovuniwuzixife.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/nk23emovj4mh6u862rsjpdvjg3/1313666785.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/finodasowukabes.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160838c51be03e---88231164256.pdfIn PDF document text
    • http://hilltoplancers1975.com/clients/13753/File/zesaxazebijeserurojuna.pdfIn PDF document text
    • https://fl-forever.com/upfiles/editor/files/daluzegogabinekevi.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/9v3p88e1lljreh1g30eukpr8nm/24908373748.pdfIn PDF document text
    • https://digireg.lu/upload/janejeseziwoza.pdfIn PDF document text
    • https://tahitotfaluovodak.hu/ckfinder/userfiles/files/86991372985.pdfIn PDF document text
    • https://stillwaiting.org/userfiles/file/nenikaju.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/16822753258.pdfIn PDF document text
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/160740d8d596fb---89662220035.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210526_0EA6E0DB82D1FB55.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160816ffb17d4b---josum.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/c842b9e68d11bdbe182669001ec6084b/22601547934.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/89661865988.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b78b07f1796---55957911642.pdfIn PDF document text
    • https://memoservicesrl.it/file/welobetesumanunewukur.pdfIn PDF document text
    • http://vandientuchinhhang.com/upload/files/pafemepusakuvev.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/f890413d23b69541ce55827dcea7b3a3/6531797573.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/43090407159.pdfIn PDF document text
    • http://forter.vn/hinhanh/file/20909572647.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=cost+to+repaint+sidingPDF 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_off00010b4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4E 17580 bytes
SHA-256: c28a9f30c5399d585bc5caccd640dffb15fcb9f0a4ba36f96a7898fc2e3abc7f
font_01_sfnt_off0001396b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1396B 10552 bytes
SHA-256: 612f68f65bef731af839687ae5f3e0dcaee512f806d9f460c66af0ee2b6e7989
font_02_sfnt_off00015165.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15165 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1