Malicious PDF — malware analysis report

Static analysis result for SHA-256 236a2ec4d35ac91f…

MALICIOUS

PDF

74.4 KB Created: 2021-09-17 19:19:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5a62cf61ffa947f914b5cd1a4889c40d SHA-1: c3ae3425a12c473e60c2e44f3fe2d29e45676983 SHA-256: 236a2ec4d35ac91fee49390d9a29534624ac8602be30dc71b85a38e70789c3d0
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which are part of a link farm hosted on disposable domains. Heuristics indicate a high likelihood of malicious intent, with ClamAV specifically detecting it as a phishing trojan. The presence of embedded JavaScript suggests an attempt to execute malicious code, likely to facilitate further compromise or download additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://laborke.ru/uplcv?utm_term=gb+instagram+download+apk PDF link annotation
    • https://m-isc.com/userfiles/file/45473405453.pdfIn PDF document text
    • http://ohsongpharm.com/ckfinder/userfiles/files/4847140250.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/pokelatuze.pdfIn PDF document text
    • http://zsdbiopharm.com/upload/files/43372794383.pdfIn PDF document text
    • http://doremimarlikinsaat.com/userfiles/file/85707143080.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021911112633206.pdfIn PDF document text
    • http://dae-young.kr/upload/fckeditor/file/42423502157.pdfIn PDF document text
    • http://klhl.com/userfiles/file/bijitijerusapur.pdfIn PDF document text
    • http://slsnn.ru/content/file/mogejavos.pdfIn PDF document text
    • https://luathoanghuy.com/uploads/files/27473695677.pdfIn PDF document text
    • https://clinicscrm.com/img/files/sizawubafifedalakok.pdfIn PDF document text
    • https://www.q-jin.ne.jp/ckfinder/userfiles/files/duzitanufotof.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/12694470756.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/48088000617.pdfIn PDF document text
    • http://www.fd.ntou.edu.tw/ckfinder/userfiles/files/90186396192.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/235569955.pdfIn PDF document text
    • http://linza-market.ru/upload/files/liwumoxipegupigigulaluwo.pdfIn PDF document text
    • https://www.dgaspcsm.ro/ckfinder/userfiles/files/fobokoxit.pdfIn PDF document text
    • http://mundori.com/js/ckfinder/userfiles/files/sizidolep.pdfIn PDF document text
    • http://korytnica.net/data/files/jusibunawifal.pdfIn PDF document text
    • http://magic-mugs-factory.com/uploadfile/files/wedazivonopitemuxatuwu.pdfIn PDF document text
    • https://wotfiles.com/ckfinder/userfiles/files/73174860763.pdfIn PDF document text
    • http://soepcentrale-dekeyser.be/userfiles/file/62192986639.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/b4dd32d7226bee42094ab7d05a425aa0/gogeso.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_off0000bf88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF88 10960 bytes
SHA-256: bacaa109a81aa4ae64014ab786958478152b29382100d12976f84b9673d3e10a
font_01_sfnt_off0000d896.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD896 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A8 16860 bytes
SHA-256: f06b076cee75cbb8852f91270cb4c03ec81f8c9c69f0ea5b20b49f19bbf48a6d