Malicious PDF — malware analysis report

Static analysis result for SHA-256 847aa58f5876fdf9…

MALICIOUS

PDF

76.7 KB Created: 2021-09-03 00:52:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2ee3f6bfcc04c667b77e853630cd63b1 SHA-1: 4e1a0451ec988dbf2e9f76dbd76c7b46240f27bd SHA-256: 847aa58f5876fdf966a57bb4ccb6362b97d77151ba9835f1bded842118b2c136
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the sheer volume and nature of the URLs suggest a malicious intent to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 5

  • 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 http://1984wnhs.com/clients/2/25/250e0aaa51dad033202e6c34d8602b4d/File/22464973616.pdf In PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c64c653a1bf---kogiw.pdfIn PDF document text
    • http://studiolaviano.it/userfiles/files/16141460294.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cad0480d9a---72812172384.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/xedes.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210623_E2DDDE683A14CD0B.pdfIn PDF document text
    • https://rosycaffe.com/file/jukawu.pdfIn PDF document text
    • http://www.golfusa.be/userfiles/files/pujagexurokik.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/ganeje.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/xotuki.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/kudamapikivolufewefa.pdfIn PDF document text
    • https://www.crqp.ch/ck/ckfinder/userfiles/files/47304377681.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e9aa6162a---71354044933.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/58a3a38b224076c2154b9a6b92044447/3272294345.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/vanet.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160fbf03f2e121---jovadafotalitupurujujor.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/iketrh1n69t4l59qfeak77vve2/damiwig.pdfIn PDF document text
    • https://mauspro.net/upload/files/kusepobuxegeb.pdfIn PDF document text
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/c1vhd5rvhtoo009f2jrugolnd7/29290274211.pdfIn PDF document text
    • http://bandenplaats.nl/cmsimages/file/27379603330.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/pkv026dqfh7p2hkct0stsrrutn/90838223604.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ab281b39f96---tokamaragawerawotubi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=adjoint+of+a+square+matrix+pdfPDF 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_off0000c324.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC324 18588 bytes
SHA-256: 4f2e0f15ff5093504c8d2edfed98c62ffd0afe71e139ab066b8671f3c81a29fa
font_01_sfnt_off0000f3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010bf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BF4 11072 bytes
SHA-256: 8ac5b84057627b5b1b6a931b33330695f1b918f2a2c34c1612c7f7f1ec5b9d99