Malicious PDF — malware analysis report

Static analysis result for SHA-256 a040ba316353dc25…

MALICIOUS

PDF

69.2 KB Created: 2021-09-28 10:50:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9ca6f89b9aff5224f66bba2045053824 SHA-1: d346bf80b704e2eefd4965fd48398095f28c1449 SHA-256: a040ba316353dc250158af3b1688309855b2875cfbf5fc12fbf42b53bec9e777
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised websites and disposable hosting, with one URL specifically mentioning a 'free download' lure. Although no scripts were directly extracted, the nature of the URLs and the PDF format suggest it's designed to redirect users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://laborke.ru/uplcv?utm_term=dlc+the+sims+4+gratis PDF link annotation
    • https://smilewax.tw/uploads/files/202109241201495545.pdfIn PDF document text
    • https://cargoservice.pl/cargoservice/userfiles/file/71098805290.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/18se91il1uc84f2lvrqk26bhd0/11126977677.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/lebajipunezorujogo.pdfIn PDF document text
    • https://ahha.az/userfiles/file/9419144818.pdfIn PDF document text
    • http://thietbiotoviet.com/Images_upload/files/jevabuvopuvigorogezo.pdfIn PDF document text
    • https://thietbivesinhsonhoa.com/webroot/img/files/vajidebozekojulanejo.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16131bcc307520---45155570302.pdfIn PDF document text
    • https://mandarinusa.com/userfiles/file/1630914408.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/vuvoguzizugu.pdfIn PDF document text
    • http://freeorden.com/media/file/74374340931.pdfIn PDF document text
    • http://dataprint.ie/uploads/file/2779903092.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f77ab53d36---sejotin.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/47e72d934814f255f4da4cdfa32f060c/dudubiwifijatewi.pdfIn PDF document text
    • http://www.psoealora.es/ckfinder/userfiles/files/fajumolajawofu.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/luwimegikemuvi.pdfIn PDF document text
    • https://contact-house.com/fckeditor/upload/file/81165939133.pdfIn PDF document text
    • http://isotech.si/uporabnik/file/kezowezinapivavasidetedud.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/ponorovikatisarujosixadig.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/zixesetubijokafijaz.pdfIn PDF document text
    • http://24cvety.ru/upload/files/76581686665.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/161331cd65f3f1---sunogu.pdfIn PDF document text
    • http://nanumed.ro/uploads/files/muvejuto.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/saxedifip.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_off0000b079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB079 10532 bytes
SHA-256: ba59795a2db47ad2935444c01f0e1f399ca1fafead750330a5796b759ad4a812
font_01_sfnt_off0000c887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC887 15476 bytes
SHA-256: 841d36a7fca844088834f1961c360c48cdb169be6a3e33039e9b5717520115e6
font_02_sfnt_off0000efd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1