Malicious PDF — malware analysis report

Static analysis result for SHA-256 8961c304d6d4cd0f…

MALICIOUS

PDF

89.1 KB Created: 2021-10-07 01:19:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 57f2b2b6f59099e1408683d72771c5c6 SHA-1: 6b2aebdc66094129307034ee456f8155882a14a3 SHA-256: 8961c304d6d4cd0f7a60a9b9af3e08761b93d14be25dc01a364b71f7e6a07226
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous embedded URLs pointing to compromised or disposable domains, which are commonly used for phishing or distributing further malware. The presence of multiple link farm heuristics and the detection of external URIs strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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 http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/35591507690.pdf In PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/49298423867.pdfIn PDF document text
    • https://rowadalbyt.com/userfiles/files/36701231859.pdfIn PDF document text
    • http://www.grupoaccs.net/ckfinder/userfiles/files/mufifavat.pdfIn PDF document text
    • https://lrdreamteam.com/files/files/file/InfoProduct/file/75414686524.pdfIn PDF document text
    • https://netkat.in/ckfinder/userfiles/files/zuxukufi.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/c188139160da9ad34fdf0bfc836f348a/97118543767.pdfIn PDF document text
    • https://profession-your-dr.com/uploads/files/202109230520584248.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0f48e5875---12526070784.pdfIn PDF document text
    • https://campermagazine.tv/public/file/xisuxopesariludovije.pdfIn PDF document text
    • http://candientushinko.com/images/file/lukofowenumivi.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/82579869970.pdfIn PDF document text
    • https://vwb.mrv-educationservices.com/content_file/files/29739960278.pdfIn PDF document text
    • http://kerekesvillszer.hu/UserFiles/file/bupanuteka.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/77571274642.pdfIn PDF document text
    • https://wrd13.com/force/file/72063080147.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/99411680549.pdfIn PDF document text
    • http://ijfbn.com/editor_up/gasofedozalamowe.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16156741e98126---gavafezopolewipexenovo.pdfIn PDF document text
    • https://cowichanmusicfestival.com/userfiles/file/davunuwej.pdfIn PDF document text
    • http://geriatriccarenewjersey.com/userfiles/files/mipafirigubisuforulez.pdfIn PDF document text
    • http://godsownproperties.com/userfiles/file/xideletolalulokovewikas.pdfIn PDF document text
    • http://123podkrovie.sk/editor_uploads/files/85838567934.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/pebibametuzerad.pdfIn PDF document text
    • http://codienlanhminhquang.com/upload/files/wibegawowofogezirusuzur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=letter+from+birmingham+jail+conclusionPDF 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_off0000f510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF510 11112 bytes
SHA-256: ff926c52fce063827cbc833eac358e277081341e77c515a47243161390e8c93c
font_01_sfnt_off00010ebf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EBF 18608 bytes
SHA-256: 6b4d8c9893ed66f3f06ae0bd21ad261d37c18a2515e425d28bfe9c0807aa98d1
font_02_sfnt_off00013f18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1