Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a5961409750ba82…

MALICIOUS

PDF

93.8 KB Created: 2021-09-14 22:49:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 522278a9242405619080a7b682a86db6 SHA-1: ba9ea6c51407af8b7f610f97562363f7fa0e9f9d SHA-256: 7a5961409750ba8234caeffbfe9cbf948c70a928bd3507def18303ee2d80334e
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads. The presence of numerous URLs, including one with a 'utm_term' parameter suggesting tracking, reinforces the phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • 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.
  • 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://huntic.ru/uplcv?utm_term=the+walking+dead+season+11+episode+1+123movies PDF link annotation
    • https://libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/belatakexudozekurujofevak.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/13824117541.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/mipuzuvide.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/dudirip.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/91689969664.pdfIn PDF document text
    • https://hiroyoung.com/data/files/57389340626.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/nedijapixinosobimuxidi.pdfIn PDF document text
    • http://aromacosmetics.bg/assets/userfiles/file/61659230587.pdfIn PDF document text
    • https://vinniescustoms.com/userfiles/files/banezumizawe.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/i1ed8b8qrmnl1fne14ssk3gqul/34596306867.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b8ae20318---91439117057.pdfIn PDF document text
    • http://adria-ex.com/images/blog/file/3368000502.pdfIn PDF document text
    • https://thuanxuongmonmb.com/admin/webroot/upload/image/files/naxazax.pdfIn PDF document text
    • http://wedding-box100.com/uploads/files/202109040346307411.pdfIn PDF document text
    • http://kotrackusa.com/fckedit_file/file///20210909_20_52_35.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/girotuki.pdfIn PDF document text
    • https://radio-aurea.eu/files/file/guvujewuxume.pdfIn PDF document text
    • https://paeonia.ch/userfiles/files/ruwukojerozeg.pdfIn PDF document text
    • http://nurugelexport.com/ckfinder/userfiles/files/89309646347.pdfIn PDF document text
    • https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/63018538224.pdfIn PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/fosunoledewadulux.pdfIn PDF document text
    • https://afritransport.com/app/webroot/files/file/28864320160.pdfIn PDF document text
    • http://77owship.netsociality.com/upload/files/88851396008.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16134c66cc2148---folusovesunowax.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_off000100bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BB 11192 bytes
SHA-256: dc411ad5876baa319be99f988689304ddf5434477b09503214cdeaa263d0cc01
font_01_sfnt_off00011aa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AA4 20428 bytes
SHA-256: 90e3383164e8ca491a8471c13999951752f55a759ec6ba9150e135f35f06f179
font_02_sfnt_off00015101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15101 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1