Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ac05b60ed4a21ea…

MALICIOUS

PDF

81.4 KB Created: 2021-09-13 19:51:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 402dde76669bbf80ae338b121bfd9d1a SHA-1: 9834d9dd265d6dcc837691427d0a6c13cacb4f15 SHA-256: 3ac05b60ed4a21ea4784e581f2e2d907cc874e9563ddd2a41ffc621f89faf371
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with many pointing to potentially malicious domains, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a common phishing or malware delivery technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • 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.
  • 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://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/suzokenarosi.pdf In PDF document text
    • http://dreesmann-foto.de/userfiles/file/42074653455.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/31949409023.pdfIn PDF document text
    • https://cristalparkhotel.com/ckfinder/userfiles/files/75551317445.pdfIn PDF document text
    • https://dimensioninteractive.com/WYSIWYGImage/file/95148729547.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/naxenoselese.pdfIn PDF document text
    • https://www.sexualaufklaerung-schule.ch/ck/ckfinder/userfiles/files/kenidaneboxoweworefuta.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/pekapipuwizara.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/44262019335.pdfIn PDF document text
    • http://vanguardhungary.hu/userfiles/file/87545454563.pdfIn PDF document text
    • http://eaupureinternational.com/userfiles/file/duwirupodeneti.pdfIn PDF document text
    • https://aarushimukhwas.idealviews.com/userfiles/files/87076868014.pdfIn PDF document text
    • http://ruiqingchem.com/upload/files/87421324204.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/17876361052.pdfIn PDF document text
    • http://pastadimatteo.com/ckfinder/userfiles/files/69210724196.pdfIn PDF document text
    • https://luathoanghuy.com/uploads/files/vonag.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613666b80cc1c---22859899706.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/88359773976.pdfIn PDF document text
    • http://jcbcharpentebois.com/ressource/site-image/files/60553655429.pdfIn PDF document text
    • http://qiangka.com/ckfinder/userfiles/files/livozejukanavawunirefazef.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/50166877274.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/vijudonilefowijiwugupo.pdfIn PDF document text
    • http://dorapeyzaj.com/userfiles/file/xudidubumudusido.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=instagram+followers+increase+app+for+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://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_off0000d912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD912 11000 bytes
SHA-256: 6d3fc67c8178309fd9866a684204ee9b8bc17c810b580c0f53d11c6144ea749a
font_01_sfnt_off0000f270.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF270 17444 bytes
SHA-256: cc59dda1f53bcaf9fd3076cb465f537b977c41474ad098c7e1c3efce42e9f270
font_02_sfnt_off00011ff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1