Malicious PDF — malware analysis report

Static analysis result for SHA-256 75431c35b6897b6c…

MALICIOUS

PDF

73.8 KB Created: 2021-09-21 19:27:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 00b603e4859869b1647a12ef5818297b SHA-1: 53ebf8d2d572f44dbe9717d36154d72e6909de2b SHA-256: 75431c35b6897b6c131271a4edb3de63c2af815a5d357c6281936c2afff7f586
164 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous external URIs, many of which point to compromised CMS uploads or are hosted on disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of a 'download' button lure further supports a phishing or malware distribution intent.

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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://drafthe.ru/uplcv?utm_term=how+i+run+android+apps+on+pc
    • https://living-stone.lu/userfiles/files/jadixawinuvara.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/jg4emp5iht5k6q7oa40r2om1fq/fulobiludukikuzi.pdf
    • http://ghettaetamionarchitetti.it/userfiles/files/tebabenosinurud.pdf
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210907002347.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d64a16a1b6---73757285874.pdf
    • http://unicaconsultoriarh.com/images/files/vetitexoloxigatosikijuze.pdf
    • https://griby.biz/ckfinder/userfiles/files/tasetizovipuwepadolabupo.pdf
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/fisarumilituloxoluwuvazin.pdf
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/domujisudix.pdf
    • http://familie-schiecke.de/images/file/nosekovebe.pdf
    • http://villa-margherita.biz/userfiles/files/xuzipoditixak.pdf
    • https://kabelkyaobuv.sk/editor_uploads/files/jamaminifebekupozi.pdf
    • http://saveursetsavoirs.fr/image/file/wifatibujekozazogupafubaz.pdf
    • http://szao-spb.ru/images/news/file/xufipodevuvilonuf.pdf
    • http://photopuzzle.net/userData/board/file/68553493644.pdf
    • http://ordineveterinarireggioemilia.it/userfiles/files/20712105476.pdf
    • https://hamayeshniroo.com/shop/file/4157757580.pdf
    • http://www.darvidproperty.com/news/file/jonaxujofuzuzozatewij.pdf
    • https://nabsangram.com/userfiles/file/wigazifexuderevigebadu.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/7hq9tudn9djdgsqoa5cjhfc0t1/rerusuwul.pdf
    • http://phamtrangia.site/upload/files/63405547998.pdf
    • https://fasleh.net/Files/files/rawedutofe.pdf
    • http://thepducphat.com/upload/files/mijotoposebenijaja.pdf
    • http://fitviewer.info/files/file/tifezikejedupoxuka.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bebb.bin
38f0e5b1bb267d310ecef52750f16736715aff8b3435f82bbf42460c4febe1dc
pdf-font-stream PDF embedded font (sfnt) at offset 0xBEBB 10408 bytes
font_01_sfnt_off0000d664.bin
a9c79a2111c96454ced2537d5430aaa5b019af5a9fbca27bbee7e237aec5b662
pdf-font-stream PDF embedded font (sfnt) at offset 0xD664 16636 bytes
font_02_sfnt_off0001014f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1014F 16792 bytes