Malicious PDF — malware analysis report

Static analysis result for SHA-256 729ecf62f81fa8c3…

MALICIOUS

PDF

96.7 KB Created: 2021-09-17 14:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 5bfbd9e4d66491d274eac1dd2eec03cf SHA-1: 597471b913197190d4ed438a30ba72271953b8dd SHA-256: 729ecf62f81fa8c3303a84c680d4d6453f0849ff838fadeffe120e21637dd0e2
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users. The presence of numerous external URIs, many pointing to disposable domains and employing UTM parameters, strongly suggests a phishing or link-farming campaign. The ML classifier and ClamAV detection further confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9888

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
  • 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.
  • 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://infrive.ru/uplcv?utm_term=stephen+king+danse+macabre+pdf PDF link annotation
    • https://edu-mate.kr/_UploadFile/Images/file/57698349557.pdfIn PDF document text
    • http://f-kcc.jp/user_data/userfiles/files/wanev.pdfIn PDF document text
    • http://denprokhorov.ru/images/file/77257662746.pdfIn PDF document text
    • http://rapabzenec.cz/obrazky/files/67609829930.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/vakijowikotorute.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/viludajumo.pdfIn PDF document text
    • http://recviem.ru/img/upload/58252933931.pdfIn PDF document text
    • https://sunpower.lv/ckfinder/userfiles/files/87127696536.pdfIn PDF document text
    • https://perfumes.dropship-tracking.com/userfiles/files/pitupajidolusu.pdfIn PDF document text
    • http://hightopeducation.com/cms_uploaded/file/18126598974.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/rofalupubu.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613556e45f525---garavewujedosotorede.pdfIn PDF document text
    • http://ristoranteyuri2.com/userfiles/file/69230122531.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/rajudamelaru.pdfIn PDF document text
    • http://xn--90afqerdlt1f.xn--p1ai/admin/ckfinder/userfiles/files/dojuwawabuzokopexitude.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/jimubavisajagitulanani.pdfIn PDF document text
    • https://batikatravels.com/userfiles/file/bowiwururixatal.pdfIn PDF document text
    • http://metamorfozyayincilik.com/userfiles/file/8516204882.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/17/fowido.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/65141345597.pdfIn PDF document text
    • http://motopujcovnateplice.cz/userfiles/file/88051567893.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/xupireralenuk.pdfIn PDF document text
    • http://naplesredeals.com/userfiles/files/zubajexuradobila.pdfIn PDF document text
    • https://shinaltd.ru/images/file/19739507632.pdfIn PDF document text
    • http://tichdiem.surecare.vn/uploads/userfiles/file/92250161542.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/777226b5f5ffdd9b5bae2b393af4d4da/53013020005.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_off00011300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11300 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012b17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B17 11208 bytes
SHA-256: 075921871efd7a1ca6c79fbf6d774279c338ba59f92a703aa06d12576e8a4804
font_02_sfnt_off000144b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144B0 18652 bytes
SHA-256: 9f756bb312e2cdb3d9d60dae9a12fc1e047c0b6bceea1d9d788823cb1dcddc42