Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b9c61a1cc1b604f…

MALICIOUS

PDF

84.1 KB Created: 2021-09-09 23:51:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 99f5b2d6815874a5c0b4df73c49f0474 SHA-1: b63a76548d56c509a9ae7e8e31c1c72e78e02da3 SHA-256: 3b9c61a1cc1b604f204ef4c9a66ce101ba823b2184aa008cd4c7bf5bf09544e7
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm with numerous disposable URLs. The presence of a 'download button' heuristic suggests a lure to trick users into clicking on these links. Although no scripts were explicitly extracted, the PDF structure and the nature of the URLs indicate an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://labonscafe.com/userfiles/fowufotasotipowef.pdf In PDF document text
    • https://badrivishal.com/media/wuzokisinuresa.pdfIn PDF document text
    • https://jagamimpi.info/contents/files/zaponosaniwezudigupofiv.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/rojetid.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/dukulakejokulosudimuwaz.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/fodewiji.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/viberosavejoxeru.pdfIn PDF document text
    • https://ryokanclub.com/FileData/ckfinder/files/20210910_D43C5CAF1D52C470.pdfIn PDF document text
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/15619167207.pdfIn PDF document text
    • http://groupelamiri.com/uploads/FCK_files/file/zumedenobopukiwosepuditub.pdfIn PDF document text
    • http://nasfthr.com/userfiles/file/41527381306.pdfIn PDF document text
    • https://ecoolteh.eu/galeria/file/51353474609.pdfIn PDF document text
    • http://milkexim.ru/imgeditor/file/balojixapifegusolarizax.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/44501303691.pdfIn PDF document text
    • http://avandcie-energy.com/ckfinder/userfiles/files/zoparofekazepogi.pdfIn PDF document text
    • http://streathamtaxi.com/survey/userfiles/files/lefuditit.pdfIn PDF document text
    • http://getsolarny.com/userfiles/file/87171889704.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f954a27318---baxebopimasugimuneza.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/rusivawufujigasonaxob.pdfIn PDF document text
    • https://pleasanton.com/wysiwygfiles/file/sizekiju.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/damuzejofevirovixewozajus.pdfIn PDF document text
    • http://simoncaulkin.com/images/88689041046.pdfIn PDF document text
    • http://julianina.dk/upload/file/47891480964.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/fajazafipar.pdfIn PDF document text
    • https://polymadeniyaglar.com/fckeditor/userfiles/file/33720152402.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=chakravyuh+full+movie+downloadPDF 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_off0000e4c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C3 10840 bytes
SHA-256: 85b0deea6395af3f7f5ea6c5e0c3c618cd819461a7171c8eea6a5ff7eef36cf7
font_01_sfnt_off0000fda7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115B9 17468 bytes
SHA-256: 453c9b1f294a3aff693c003aad6edeba8dd3223c0033393c0484eb1988768e34