Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb4f32a314de526b…

MALICIOUS

PDF

84.7 KB Created: 2021-09-15 15:59:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c97642632256d8036a84bdbaa667966a SHA-1: ac204ac553f9c6f2e28382f24f07fdcfc605118a SHA-256: cb4f32a314de526b489bf1f287b833afdc6c153b3dfd23ed877b68a51a549d28
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple URLs pointing to potentially compromised CMS upload directories and disposable hosting. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous external links strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://obras.ru/sites/default/files/uploads/zogomozajigowadijipiniki.pdf In PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141e7282e2f2---woxavewevi.pdfIn PDF document text
    • http://manu-transport.com/documents/file/nadarowavegovimigased.pdfIn PDF document text
    • http://www.cpnatacao.pt/backoffice/ckfinder/userfiles/files/50121420417.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/161392faf62cbe.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/94385819439.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/dukowajijupazaxuvof.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/vegasudivodija.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131894faa13e---zuvojemexesexubupatereb.pdfIn PDF document text
    • http://eszixv.hu/ckfinder/userfiles/files/59082570238.pdfIn PDF document text
    • https://kisikana.hr/UserFiles/files/7522006038.pdfIn PDF document text
    • http://edwindijk.nl/home/edijk/domains/edwindijk.nl/public_html/uploads/file/databeni.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/58153821313.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/mitijimejojipolubukizulib.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/regaro.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/08b0fc1753288e8d78da83b6f00b258f/27210181539.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/03de254c51380f02dcbf1c420d1543fc/perawiza.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/s4mm1q7nhlu4bp2osvd38015s3/51761437810.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/kiwirudofekolorovin.pdfIn PDF document text
    • http://music-saikung.com/ckfinder/userfiles/files/174821042.pdfIn PDF document text
    • http://sahcarpets.com/userfiles/file/93708024251.pdfIn PDF document text
    • https://bawauang.com/contents/files/xugafowi.pdfIn PDF document text
    • http://czyxchem.com/upload/files/54549874976.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/saxegevozagipavamipipor.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/zagavilunozomufidara.pdfIn PDF document text
    • http://pro-elec.ru/ckfinder/userfiles/files/66085441176.pdfIn PDF document text
    • https://showdetango.com/bafa/userfiles/file/53310759686.pdfIn PDF document text
    • https://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/55644460661.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=digging+poem+themePDF 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_off0000e6c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEDD 10224 bytes
SHA-256: f7cddff32bc4fdd0c5628d7d94fc9189e1249bce129909eab30fbd1281d45f67
font_02_sfnt_off00011590.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11590 18168 bytes
SHA-256: 190e257c56391418cc4bbec14999186b690e9efea7b3afec39c683da4e1aecec