Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a5a157d9ca5dc29…

MALICIOUS

PDF

85.4 KB Created: 2021-09-16 00:00:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fe1b66258f01783997a82ec520c31193 SHA-1: 55cd021c1142085b0779d476fe00573a4fd4393f SHA-256: 3a5a157d9ca5dc29195e729b032dc5c67686f58bc7d815cb5dedabdb26a506f3
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it uses a browser extension installation lure, a common social engineering tactic. While no scripts were directly extracted, the presence of numerous external URLs, including one with UTM parameters suggesting tracking, points towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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 https://chcial.ru/uplcv?utm_term=how+to+take+a+screenshot+on+your+android PDF link annotation
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/573d4168b53470c7f33e2d773817b75a/vobezuzutukawab.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/20799541291.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/14493702644.pdfIn PDF document text
    • https://pratham.one/file/46673727653.pdfIn PDF document text
    • http://khojedu.net/userfiles/file/32855332718.pdfIn PDF document text
    • http://4rrecycle.com/files/file/23231871968.pdfIn PDF document text
    • https://dwitunggaljaya.com/sitefiles/file/sedofilebe.pdfIn PDF document text
    • http://vinhhangvien.com/upload/files/20706777490.pdfIn PDF document text
    • https://samsungdvm.net/upload/ckfinder/files/63025542309.pdfIn PDF document text
    • http://satakantaresort.com/user_img/files/63835264276.pdfIn PDF document text
    • http://cascad-trans.ru/files/68927634895.pdfIn PDF document text
    • http://goldnumber.info/userfiles/file/tugazevivenenumovum.pdfIn PDF document text
    • http://sghr.ca/upload/ckfinder/files/zewosegimob.pdfIn PDF document text
    • http://probeg2000.ru/files/userfiles/files/23833546486.pdfIn PDF document text
    • https://maintogelonline.bet/contents/files/31138218414.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/11054358545.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161425ece95f3c---zodigulokepewamakivu.pdfIn PDF document text
    • https://webmenuplus.com/images/file/5155447391.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/48526956345.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/83886513790.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/63941649859.pdfIn PDF document text
    • https://lanhcongnghiepthinhphat.com/upload/files/befaxoratudener.pdfIn PDF document text
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/volojejusuketope.pdfIn PDF document text
    • https://mimpiindah1.com/contents/files/42494118620.pdfIn PDF document text
    • http://gloria-eurex.com/images/blog/file/26754339108.pdfIn PDF document text
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/74042360828.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_off0000e4d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fcec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEC 10804 bytes
SHA-256: c37ed861c13ec4be2328e02958a5613cb9a843185fb875f86bc92b575ecf8994
font_02_sfnt_off000115d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D4 19136 bytes
SHA-256: f02575e2f458e4f8ccc97e0474928d7d1f9bf8968f11eafdf1847f4470e3eebf