Malicious PDF — malware analysis report

Static analysis result for SHA-256 735b328beece7fcf…

MALICIOUS

PDF

80.5 KB Created: 2021-09-17 04:18:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 720bcec2fe5a451327d3394080fa43fb SHA-1: 592b3bdf4bfb78c00f21b802a2727f1e3c069868 SHA-256: 735b328beece7fcfd6168454205d09dca50ddb38433a78ac8722e64c0d1b5fff
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, with specific heuristics indicating it functions as a link farm and a lure for password-protected archives. While no scripts were directly extracted, the presence of numerous unknown URLs suggests an attempt to redirect users to malicious content, potentially a second-stage payload. The document's structure and the 'SE_PASSWORD_ARCHIVE_LURE' heuristic strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://asijskepotraviny.cz/files/file/pelolureruwadene.pdf In PDF document text
    • http://old.arcnet.org.tw/ckfinder/userfiles/files/jutosikos.pdfIn PDF document text
    • http://mdtrend.hu/files/file/23561700954.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/jokepuxavujekososativi.pdfIn PDF document text
    • http://beiks.info/public/file/nemuzoruzozuzotivokez.pdfIn PDF document text
    • https://greenlandpark.com/uploads/files/takilugawowozul.pdfIn PDF document text
    • https://auto826.vnpec.xyz/uploads/files/jikavuvogukaf.pdfIn PDF document text
    • http://ottuk-e.org/userData/board/file/dufem.pdfIn PDF document text
    • http://spbi.cz/res/file/simokelemurumusexeme.pdfIn PDF document text
    • https://oceanflowerhotel.com/uploads/image/files/61244277292.pdfIn PDF document text
    • https://hirurgija.me/files/8614003498.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109150937592497.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/66058201992.pdfIn PDF document text
    • http://gazdalkodjokosan.hu/img/userfiles/file/53874704129.pdfIn PDF document text
    • http://owop.challengersports.com/ckfinder/userfiles/files/migowaxagezetatalu.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/woxegufojoresaluvi.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/88761707561.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/madozamo.pdfIn PDF document text
    • https://borgopitti.it/userfiles/file/11440888073.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/3db5fe79a2c7ba4420aeebbfe8a75ef6/zujuki.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613f031088935---21466995207.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/263535111.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/44902996937.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/8406995547.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+read+ebook+on+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_off0000d731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD731 17496 bytes
SHA-256: 9f51d393c9a9e098ef343a6ba5b7e4bb853432405b47f9a5d3b482e7653c5268
font_01_sfnt_off000104e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E9 10336 bytes
SHA-256: 5c2b914bf2318d963c8f3b72ec3f42f38064c1c91732c6faf62ddf94056e9bba
font_02_sfnt_off00011c53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C53 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1