Malicious PDF — malware analysis report

Static analysis result for SHA-256 841f1854e69e1098…

MALICIOUS

PDF

74.9 KB Created: 2021-09-04 01:53:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 0a6c8de76b9a6441214446af581e1ffd SHA-1: 00f449d95fc3b48fe5357daf5de0eba71952f8ca SHA-256: 841f1854e69e1098c28ba72615c2c80dc42cf0e824baf904355f9ac08ec86835
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/j1kplafcv8498u2u5d4kbeunvr/27302182847.pdf In PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1607e32365911f---lofuduso.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/velivapegibafirag.pdfIn PDF document text
    • http://onishi-kyosendo.jp/archive/1924609467.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16080c109a008c---niwuw.pdfIn PDF document text
    • http://55pluscommunityspecialist.com/userfiles/files/povolitepusatapovuzaxaz.pdfIn PDF document text
    • https://amitadevnani.com/userfiles/file/dafaragudokewok.pdfIn PDF document text
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/119652c5f7a32ad661ede4073bf92b38/tabije.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/fosomumijusodetuduromevof.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/16790578077.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/cdcaeec0da03129c1eba356b17abe329/vipuwevowebiloj.pdfIn PDF document text
    • https://glory-aqua.com/userfiles/file/6829831166.pdfIn PDF document text
    • https://mbamantra.com/ci/userfiles/files/20583590672.pdfIn PDF document text
    • https://bravo-hk.com/userfiles/file/10095590603.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/tojaxebamozaxugowuri.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/52681863158.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606c660f32421---baximaraxumoj.pdfIn PDF document text
    • https://tideandtigers.com/ckfinder/userfiles/files/13575740024.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d679549773a8d66606c65fc1567ecd1f/fexitutulogizefakarifovox.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/ddt6dp9gil614a8t1mjd62rqmf/lewiliketufukosadem.pdfIn PDF document text
    • http://trungnguyenjsc.vn/uploads/image/files/gesunemapolijapumebo.pdfIn PDF document text
    • http://skpizzasubs.com/uploads/files/22417413856.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=consonant+sounds+worksheets+freePDF link annotation
    • 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_off0000c217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC217 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA2E 10624 bytes
SHA-256: a507c47c7582432cd1b064e6342572661e63c86afc05d4292360f2760ca5c8c1
font_02_sfnt_off0000f292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF292 16828 bytes
SHA-256: 7f98e56bd8e37f733088cbbd79074e79041d92f3d6265258cc3971ed819a405b