Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf31ea03505aef45…

MALICIOUS

PDF

79.8 KB Created: 2021-09-12 19:46:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 3b0130de9d7c21f9318f6e71e4d82e04 SHA-1: efcc53d46dd943af59b05607eaf09b3479e7ad32 SHA-256: cf31ea03505aef4530056459a5be042827428dc1df3689f5c1029f34f8bc26a5
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs, many of which point to disposable domains, suggesting a link farm or phishing lure. While no scripts were explicitly extracted, the PDF structure and the presence of external links are consistent with techniques used to deliver malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://ildungrice.com/fileupload/fckeditor/file/41927306470.pdf In PDF document text
    • http://baovethanglongmb.com/upload/files/tifened.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/47298006515.pdfIn PDF document text
    • http://w-mill.jp/images/file/sepewovolir.pdfIn PDF document text
    • http://usateatop.com/_upload/files/64673087522.pdfIn PDF document text
    • http://orthopediedelft.eu/files/85309267590.pdfIn PDF document text
    • https://whiteplacard.com/UserFiles/file/92345734152.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/44881849511.pdfIn PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/37799257288.pdfIn PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/3714740772.pdfIn PDF document text
    • http://keralatravelpath.com/uploads/file/polibagufa.pdfIn PDF document text
    • https://stoneappeal.in/FCKeditor/file/nadenosefimonetomugota.pdfIn PDF document text
    • http://belv.ru/userfiles/file/jogupejoka.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/55912622907.pdfIn PDF document text
    • https://harshahometutors.com/uniformkontakt/userfiles/image/files/supomiwukegejofeki.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d9b3e5d0a3---17533231721.pdfIn PDF document text
    • http://csc0851.com/userfiles/file/20210902191648_gaufv4.pdfIn PDF document text
    • http://philipwillettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98185260247.pdfIn PDF document text
    • http://rubivina.com/Images_upload/files/kisimabopetoxuvutakegudi.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/bimupirugelirijupowusig.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/86742779462.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/fufurup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=wattpad+premium+ios+freePDF link annotation
    • https://b2cdemo.tickets.com/content/files/zorusawozatugipi.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_off0000d23b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD23B 18448 bytes
SHA-256: 526526da2d52d337d0e0866880bc063ffe2bd1377da5057c3f356fb80a8767b0
font_01_sfnt_off0001017a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011991.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11991 10600 bytes
SHA-256: 56b92673bab4a0536af234a4e7f022feadb334b2e2e58e9cf55f3b625fa3e450