Malicious PDF — malware analysis report

Static analysis result for SHA-256 991287023f790111…

MALICIOUS

PDF

70.8 KB Created: 2021-09-27 19:22:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a6837776785b5710919e724c87a37a67 SHA-1: e412f57ac7bdde109dade8af0c2c315912f0aba2 SHA-256: 991287023f790111dc0b4b7247d3c62d2aa981904b50d2d095d09ea764a1646e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, many pointing to link farms and disposable hosting, suggests a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with attempts to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://infrive.ru/uplcv?utm_term=five+nights+at+freddy%27s+simulator+download+free PDF link annotation
    • https://energooptima.hu/upload/File/58938519334.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/88189264000.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/56404949188.pdfIn PDF document text
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/kapuw.pdfIn PDF document text
    • https://efnnma.org/files/file/taturisuviwafozapu.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/wimob.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/47600600357.pdfIn PDF document text
    • http://carnavaldemarbella.com/Senegal_5/Content/files/userfiles/file/45124019903.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/roxetamam.pdfIn PDF document text
    • https://angkoronetour.com/userfiles/file/donoj.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/dedateseribemezudifepalem.pdfIn PDF document text
    • http://hoangminhceramics.com/app/webroot/uploads/files/dexowilonedosorezojaruvel.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/161443a29d1d57---tufarogezelesipojuziba.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/nokikifinepuxidixu.pdfIn PDF document text
    • http://csc0898.com/userfiles/file/20210917044345_gy5at7.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/61587061357.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/f3402f2ed2574e1c308bc298026305dd/22120548573.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/50735605769.pdfIn PDF document text
    • http://ariege.proximeo.com/ckfinder/userfiles/files/rizopiwufejajosolixetomu.pdfIn PDF document text
    • http://dongamold.com/fckeditor/upload_files/file/givomafosuzusupofileko.pdfIn PDF document text
    • http://namlinhchisapa.com/userfiles/image/file/95282686648.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/2444755289.pdfIn PDF document text
    • http://alessandrotria.altervista.org/areap/ckfinder/userfiles/files/390911147.pdfIn PDF document text
    • 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_off0000affe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFFE 16768 bytes
SHA-256: fa809151bc4ec9bfdc720c0a206f150fa3cc307bfa83f17b0a0d4e02cf724c99
font_01_sfnt_off0000db44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f35b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35B 11180 bytes
SHA-256: 4d1f9700bf88dace9d94df33d8477e4d04d34f5ca176e522bd8771ae49b79334