Malicious PDF — malware analysis report

Static analysis result for SHA-256 b151d5118202d2a7…

MALICIOUS

PDF

71.1 KB Created: 2021-06-11 05:42:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 5453339a35c17addde9cd97f2429255c SHA-1: 7897e901c5ebfdca0b12d84060cce1ffdc3f82e7 SHA-256: b151d5118202d2a7c6f33f8e89b2625a1aebacb39d2349ff92e14d3ac539855a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting, likely to distribute further malicious content or phish users. The embedded content, though heavily obfuscated, suggests an attempt to lure users with a search query for a PDF, which is then replaced by malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://catamma.ru/uplcv?utm_term=the+sun+and+her+flowers+pdf+free PDF link annotation
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ed558eda4---vurenaxaniw.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/af27m75arsjr27r2tgte6tlmft/lakexupuborol.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/88a8a87440f143534792bcf5acafdd5e/60289173248.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1f4f7b236---98330746151.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083d5858cdab---kabipuladepe.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/75859855147.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/8579363fab0923d22116554f48128da8/pimodinuditibufum.pdfIn PDF document text
    • https://coolingrealestate.com/your-home-cleaner/FCKuploads/file/80676352309.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/171dba06e316191662b5088f333f1e24/kakufonidutoro.pdfIn PDF document text
    • https://www.ideaklinikizmir.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607adde5cc8ee---61949979757.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user///file/_0298201001620169175.pdfIn PDF document text
    • https://schmitz.cz/res/file/jobefeboloxitabogara.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/3df207s8c7clvctka4kogjrj7f/milunofo.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077a5c0cb894---57784525004.pdfIn PDF document text
    • http://chithanhplastics.com/uploads/userfiles/file/saxebajimebogaletisizoze.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/zexanejo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c9b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9B0 4924 bytes
SHA-256: 959f85ce327de65f720b2c9effaa1a9235b7fc546f6a57e89a94995ad37824d0
font_01_sfnt_off0000da6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA6F 11692 bytes
SHA-256: a3a837fa5440ef674f3cb2f242feffb46609618976feec2d702a32f5d813bcfe
font_02_sfnt_off00010196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10196 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378