Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7683ec1acea28b2…

MALICIOUS

PDF

83.2 KB Created: 2021-09-20 22:20:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 36eef108de5d834addba263f758b4882 SHA-1: a81122bfd017e5c9d90830fad86445fb5ba03d72 SHA-256: a7683ec1acea28b2533371dc27340be820c024fdd388d6385d51f9dd9409bc78
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, with high confidence. The 'SE_PAYMENT_REDIRECT_LURE' heuristic indicates the document's content is designed to trick users into believing there are new or changed bank instructions, a common tactic in business email compromise scams. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest a redirection mechanism, likely to a malicious payload or phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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
  • Payment redirection / bank-detail change lure high SE_PAYMENT_REDIRECT_LURE
    Document describes new or changed bank, wire, ACH, IBAN, SWIFT, or routing instructions — a high-value business-email-compromise pattern
  • 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://koovappadyscb.com/ckfinder/userfiles/files/74739146804.pdf In PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/73722441070.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210919001244.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/zinijibidabupagipijukew.pdfIn PDF document text
    • http://happyhanool.com/ckupload/files/42042093896.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/2392037582.pdfIn PDF document text
    • http://rjbmachinery.com/d/files/66217638000.pdfIn PDF document text
    • http://veterina-hrib.cz/user-uploads/files/zezalilejolovitutapofobux.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/88543719665.pdfIn PDF document text
    • http://sswjeans.com/files/12681513065.pdfIn PDF document text
    • https://webkapper.nl/ckfinder/userfiles/files/61253746656.pdfIn PDF document text
    • https://cobrawire.com/userfiles/files/94532039270.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/timad.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/tobidijoboganusunisoxal.pdfIn PDF document text
    • http://vanhacollection.com/images/files/24622641286.pdfIn PDF document text
    • https://porfic.com/fotos/file/bufekipuzibavejoso.pdfIn PDF document text
    • https://kham.vn/userfiles/file/luzejadeligaluganisad.pdfIn PDF document text
    • http://sov.tranovice.cz/webpagebuilder/ckfinder/userfiles/files/42714007650.pdfIn PDF document text
    • https://1tlstar.com/storage/uploads/files/87233261410.pdfIn PDF document text
    • http://www.trackls.com/application/ckeditor/ckfinder/userfiles/files/gokedi.pdfIn PDF document text
    • https://masukpt1.com/contents/files/jekimuj.pdfIn PDF document text
    • https://www.aaptuk.org/ckfinder/userfiles/files/22612079842.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/5530440475.pdfIn PDF document text
    • http://managhantasala.net/mailuserfiles/file/64613283380.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/34891555465.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/genemaboludanufademijizu.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/90483796343.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+see+if+someone%27s+account+is+privatePDF 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_off0000e068.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE068 10872 bytes
SHA-256: 5923bc9545a5ff42105481fbda182fc452f6c03fb06effc49052cac2fce1328a
font_01_sfnt_off0000f9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A0 17488 bytes
SHA-256: 50d3dd713a9a90e817700d11d7c6c9aec52eb527f5bce55b76c62445b418e9e3
font_02_sfnt_off000126b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1