Malicious PDF — malware analysis report

Static analysis result for SHA-256 8502a70983feb65b…

MALICIOUS

PDF

78.1 KB Created: 2021-09-18 15:29:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4fff984b73fd7daf0fdcc984a0410b08 SHA-1: 6e577ddfd6207547ddbfe971937913401ede2db6 SHA-256: 8502a70983feb65b7fb33ce78eaa9e1c9530064fc3f09236b17bba035baf62f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to other PDF files, indicating a link farm designed to redirect users. Several heuristics suggest these links are hosted on compromised CMS uploads or disposable hosting, increasing the likelihood of malicious intent. The ML classifier and ClamAV detection strongly indicate this PDF is malicious, likely serving as a lure for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://orcasproje.com/userfiles/file/81694276207.pdf In PDF document text
    • https://liantoong.com/archive/upload/files/tusalupekivudewowufokan.pdfIn PDF document text
    • http://vanhacollection.com/images/files/94876652608.pdfIn PDF document text
    • http://lovesenergy.com/file/bavatixorixa.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3fdb92e4f---pebusulidapan.pdfIn PDF document text
    • https://sitarasign.ir/data/file/90170627917.pdfIn PDF document text
    • http://www.trisad.kz/ckfinder/userfiles/files/natal.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/kagofamaduto.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/borifadubefopapew.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/8501737a856f869ad2dc9a2a148ab02b/97359453941.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/5382407637.pdfIn PDF document text
    • http://artikos.pl/userfiles/file/kupukaluzumatox.pdfIn PDF document text
    • http://unitekinfostructures.com/userfiles/file/navubetasalen.pdfIn PDF document text
    • http://orthodoxnews.us/file/mimekonidisubefimawuwojal.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6438d2bee---40973986136.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac78b92831---28192426719.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/luzuvalow.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/mabami.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/76082507561.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/59090037832.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3ab6a4308---puxiwababu.pdfIn PDF document text
    • https://ms02bet.net/contents/files/tirisus.pdfIn PDF document text
    • http://bavlas.lt/ckfinder/userfiles/files/14939621566.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=play+aiff+files+on+androidPDF 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://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_off0000d1a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A6 10364 bytes
SHA-256: 8f6c367e7965e02fcea55c45d595bc4d822c8f0ab6ea59e86247b0c7dec6a58b
font_01_sfnt_off0000e92b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001013d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1013D 17364 bytes
SHA-256: fcfdaa48f2c3b886373836a01c87ac9d769507ed429e8534cde89365f66164f4