Malicious PDF — malware analysis report

Static analysis result for SHA-256 a39beef8c98847c4…

MALICIOUS

PDF

70.2 KB Created: 2021-10-03 00:33:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 531d3a528d1e364470d5ca48a59b32db SHA-1: 90544db9a19da7ea317ca4cdcd4e7728899db2d9 SHA-256: a39beef8c98847c48c77802a0295080be5b455da6aacc29fe0ccc3da636a494a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document's primary purpose is to host a large number of links, potentially to evade detection or for SEO manipulation to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://allytemp.ru/uplcv?utm_term=conversion+nm+to+km PDF link annotation
    • https://badrivishal.com/media/43739571953.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155e30d5109e---jumabukuviboviwilaz.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/zisigejumolufuvazaga.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/18378244339.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/63023877801.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/kiguvapevizitivuvefuzux.pdfIn PDF document text
    • http://yeongwonenc.com/userfiles/file/64692835502.pdfIn PDF document text
    • http://paulbwatkinslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fixisaban.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/093ec0913a0b1574954357e55b8339c4/57979123776.pdfIn PDF document text
    • http://francescofesta.it/userfiles/files/verozami.pdfIn PDF document text
    • https://ximangcampha.vn/upload/files/vuvazu.pdfIn PDF document text
    • http://greenflameenergy.com/userfiles/file/86183745268.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/c7b4e1b9cc97e1b98280e4c0e293e733/84880796839.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/1206455132.pdfIn PDF document text
    • http://teifsepahan.com/files/file/bowewadijepelowukiwuzoti.pdfIn PDF document text
    • https://csn-alliance.com/data/files/laxanozizagije.pdfIn PDF document text
    • https://scalper.ir/data/files/file/22051385090.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/13310895225.pdfIn PDF document text
    • http://azs-szermierka.pl/zdjecia/fck/file/13372963766.pdfIn PDF document text
    • http://fijiembajak.com/uploads/ck_uploads/files/74912711343.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_off0000b3cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3CC 15912 bytes
SHA-256: c90d6e114ceeeb45e7aed1f7171408a92924e3cb07b2f65c74885bf47914e4b6
font_01_sfnt_off0000dccc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCCC 10248 bytes
SHA-256: 9f317a3694d1ea4c00537af6ab91fb8061c419fb63f7d53c7757946274b76611
font_02_sfnt_off0000f3eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1