Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3f1b12f85e9aef1…

MALICIOUS

PDF

78.9 KB Created: 2021-10-04 20:29:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 58411f8286da15df4e2791b22190589e SHA-1: fd7dc062ac4fe3b72bcf63bbf54eb9859f0d4235 SHA-256: b3f1b12f85e9aef1f431e21dae812e9d816c3f53f782f9619f71e23fbd82ddbb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document's primary purpose is to act as a link farm, potentially to improve search engine ranking for malicious sites or to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://archism.ru/uplcv?utm_term=yield+of+sugar+beans+per+hectare PDF link annotation
    • https://heatingboiler.ca/fck_upload/file/76218470300.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/28458401564.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/161423fbc48368---pudol.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/27372670719.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/davasuvawovubukudevul.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/90202305440.pdfIn PDF document text
    • http://sxnqx.org/upload/file/Fl202109181226195026.pdfIn PDF document text
    • http://bankerz.in/qpic/files/kapewinupiboto.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/vixogitakiduwezusiwa.pdfIn PDF document text
    • http://sjatupornservices.com/file_media/file_image/file/87959672465.pdfIn PDF document text
    • http://aqgwegfjdlk.handyfriendship.com/upload/files/80304602121.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1615102db1297b---disixotobafa.pdfIn PDF document text
    • https://orcasproje.com/userfiles/file/74785355485.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/75940696364.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/15108822415.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/80082879381.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/95784315266.pdfIn PDF document text
    • https://zhbiotech.com/CKEdit/upload/files/webumuragizozena.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/66182a79748fa6578bac41cf2cee311d/gemobidazibubuz.pdfIn PDF document text
    • http://pawsandtiaras.com/ckfinder/userfiles/files/94731442540.pdfIn PDF document text
    • https://namratalakhotia.com/userfiles/files/kewomuz.pdfIn PDF document text
    • http://yuanjiangchem.com/upload/files/85132655803.pdfIn PDF document text
    • http://makesomenoise.hu/upload/file/gixagejirexikiri.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/bakomoz.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_off0000cda1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDA1 17792 bytes
SHA-256: 41c75324d1b7403c9dcb01f44a6963d0ab228add812345ba34d839a114ed0cf7
font_01_sfnt_off0000fc48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC48 11124 bytes
SHA-256: 8c6f959a05c04bca57347534b316f695969d8f3eb640db83e8b9e89f89e58fe8
font_02_sfnt_off000115be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1