Malicious PDF — malware analysis report

Static analysis result for SHA-256 a158027c31d12209…

MALICIOUS

PDF

77.3 KB Created: 2021-09-18 02:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 79778ea232b4c216d708fc3a049568e9 SHA-1: 63930ad2f476473a470a64262ed590502e166df2 SHA-256: a158027c31d122098943aaa6d8034eea4e3e4beb94cdcebbd64af32157879fdf
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URI heuristics and the nature of the URLs indicate that the document's primary purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://garglob.ru/uplcv?utm_term=text+scanner+ocr+apk PDF link annotation
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/luloxasisowawevu.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/62830489093.pdfIn PDF document text
    • https://guclupin.com/calisma2/files/uploads/72167005340.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613045f21a951---24564165163.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013new/admindia/ckfinder/userfiles/files/58184139444.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/161450cf8ef969.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f79364734a---28865180473.pdfIn PDF document text
    • http://khonggianmang.com/upload/files/54105690641.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/gifalodumural.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/73518942631.pdfIn PDF document text
    • https://www.jakketoes.be/ckfinder/userfiles/files/12324012859.pdfIn PDF document text
    • http://secretinvitation.net/images/files/mitenuwuwoliwol.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134222c9523d---tunepoxelumokedoxajinemo.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///livosutuxu.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec18addd26---jugoketudokomadesuveno.pdfIn PDF document text
    • http://dailynewsodia.com/assets/ckfinder/core/connector/php/uploads/files/bunitezanufuwejunoro.pdfIn PDF document text
    • http://tinhdaurosa.com/Images_upload/files/savesegovenukab.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/44151759525.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/jewabuxakonoligevenulaka.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/retub.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_off0000cba6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA6 17456 bytes
SHA-256: fe8631bf213a056344b1793e5e1993e1a72aa9acba60b650840974160bd5d9b0
font_01_sfnt_off0000f8b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110CB 10388 bytes
SHA-256: e84f1282ac42d34d1ebd67828ee823a036de0f34a7ed611acaf570e4d57b16c0