Malicious PDF — malware analysis report

Static analysis result for SHA-256 90c76aa59f310bf2…

MALICIOUS

PDF

96.6 KB Created: 2021-09-16 20:09:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 2695a50bbed42eead04b01e8a0dc6e49 SHA-1: 3de7c11ccdcc574103ed4d639f89f667d1c36daf SHA-256: 90c76aa59f310bf209f97c21b66a5e8511e53f52416e68b00f66b7edfe522c8d
142 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains, indicating a phishing or malware distribution attempt. The presence of a 'download button' heuristic further supports the lure of downloading malicious content. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

Heuristics 7

  • 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.
  • 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://philabc.ru/uplcv?utm_term=farm+frenzy+3+american+pie+for+android PDF link annotation
    • https://ventadeterrenosurbanos.com/userfiles/file/zalujuvegig.pdfIn PDF document text
    • http://pasaru.com/upload/files/42619625221.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/jizemidokakevoludelaxebex.pdfIn PDF document text
    • http://laptopcuhaiphong.vn/upload/files/19621216893.pdfIn PDF document text
    • http://softtox.pl/new/userfiles/file/84120781795.pdfIn PDF document text
    • http://stsmcc.org/www/js/ckfinder/userfiles/files/56422183380.pdfIn PDF document text
    • https://candbco.com/ckfinder/userfiles/files/dinibemukijoxirilipu.pdfIn PDF document text
    • http://mywayrtk.org/userfiles/file/pavemojij.pdfIn PDF document text
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/49025375466.pdfIn PDF document text
    • http://gt-outillages.fr/ressource/site-image/files/7367360190.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-5/20210905163548635052.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/879049196613253c898ad7.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a362e97160---waninolezavuv.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021090309584073499.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/17190702873.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/toxunojiwepigewuvalaluziz.pdfIn PDF document text
    • http://snap-drone.com/userfiles/file/70455962969.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/14225260399.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/58159412953.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/23797835051.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/wulugokijeginiz.pdfIn PDF document text
    • http://hzdsbg.cn/uploadfile/1630783671.pdfIn PDF document text
    • http://creationart.hu/files/file/55566536867.pdfIn PDF document text
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/88301769103.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16136dae03f90e---21326609414.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_off0001122b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1122B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A42 10792 bytes
SHA-256: 8cceb4b063f98bed5ea5cf23b210bb1e787ace3ff17b2ca22e02a94913521ed5
font_02_sfnt_off0001431f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1431F 18868 bytes
SHA-256: 09037328d98ff316927461966d0236f3a7660ea1a38ce02f295faad1cc216b19