Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1113d51b7d70efb…

MALICIOUS

PDF

85.2 KB Created: 2021-09-09 01:10:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a07470319bff61245e829cbc1565a60e SHA-1: 1962df468536a502681cad56fa611e9df86d3d3f SHA-256: f1113d51b7d70efbbc0b3a93443c030191fd7766f0ed7b81f4aa50fb8a424c93
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs, many pointing to PDF files on disposable hosting, suggests a link farm or phishing lure. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/31080133750.pdf In PDF document text
    • http://scantech3d.com/files/69027319071.pdfIn PDF document text
    • http://www.kotolantopeni.cz/files/79230432292.pdfIn PDF document text
    • https://md-bud.pl/szklo/photos/file/75465768631.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/2716981655.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612fef63aa809---88489488627.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/26802065280.pdfIn PDF document text
    • https://iohrp.org/f_files/files/zogizo.pdfIn PDF document text
    • http://evopizza.lt/ckfinder/userfiles/files/49692575723.pdfIn PDF document text
    • http://artwatch.ru/userfiles/file/ximilotigatatones.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/xepakamekowulakutato.pdfIn PDF document text
    • https://digireg.lu/upload/nugifopiguwodavoxal.pdfIn PDF document text
    • https://nic-irq.com/userfiles/files/1282745284.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/18265213872.pdfIn PDF document text
    • http://sweed-trans.eu/ckfinder/userfiles/files/zetakawojexawimefoxe.pdfIn PDF document text
    • http://konyanincigkoftecisi.com/userfiles/file/zavom.pdfIn PDF document text
    • http://hakanhurdacilik.com/userfiles/file/95104757459.pdfIn PDF document text
    • https://metnar.pl/web/uploads/files/zeguwixumutitizuteza.pdfIn PDF document text
    • https://genegurumiraclehealer.com/userfiles/file/95667021803.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/20941044751.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/8228543672.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/49241331188.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1631135179.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/63463646177.pdfIn PDF document text
    • http://vrajacreation.com/uploaded_files/userfiles/files/kuguwimefak.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/57705973405.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=papa+hot+doggeria+hd+apkPDF 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_off0000e16b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f982.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF982 10448 bytes
SHA-256: 1429963ef9a96f65696c567817c3e6f0835e23bc19a4afad58d91e32c5c5ffeb
font_02_sfnt_off00011120.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11120 20416 bytes
SHA-256: 83e8ef9cf2caa22b059e0563a415a44754f0748d55c57b0ddffa971012b2a8af