Malicious PDF — malware analysis report

Static analysis result for SHA-256 e28dd484e3dcea85…

MALICIOUS

PDF

79.1 KB Created: 2021-09-08 19:20:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: aa90a72bf3e2b3fae40ecbc4cdc3bbd6 SHA-1: 2543ddd500f949dbec509246ea8e4a109c5df334 SHA-256: e28dd484e3dcea85be63227c3241ea580dedd99cf20cfcff22a9547438f0798c
156 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 websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics and AV detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cytokin.ca/upload/editor/file/62963158594.pdf In PDF document text
    • http://kiko168.com/UploadFile/file/20210903230506343.pdfIn PDF document text
    • https://fsbulletsandbrass.com/userfiles/files/467684409.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/47260617558.pdfIn PDF document text
    • https://nepalihemp.com/ckfinder/userfiles/files/jewazu.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b9c1d4193---93489700617.pdfIn PDF document text
    • http://fields-on-earth.com/images/blog/file/40008920903.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135d52d38508---taxatupi.pdfIn PDF document text
    • https://niagarablock.com/application/webroot/userfiles/file/38147229404.pdfIn PDF document text
    • http://ruiqingchem.com/upload/files/fekurumakirosa.pdfIn PDF document text
    • http://yoshitomo-kokubunji.com/jcfiles/file/kipekelawediwarani.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd9e02b5ac---zuxov.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/70312234581.pdfIn PDF document text
    • https://citronel.com/userfiles/files/mekususalimavamikedunizap.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0ca5dc75a---3284746582.pdfIn PDF document text
    • https://soi.icami.mx/ckfinder/userfiles/files/jodas.pdfIn PDF document text
    • http://bularz-auto.pl/images/userfiles/file/xudipak.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137510c91b52---dukamipitilalapovi.pdfIn PDF document text
    • http://wingprocess.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/5778257923.pdfIn PDF document text
    • https://hattshopping.com/admin/assets/images/ckfiles/19882685645.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/fatusokozijejibiputosemoj.pdfIn PDF document text
    • https://piauiaqui.com/ckfinder/files/97474452430.pdfIn PDF document text
    • https://www.lsv-wittlage.de/ckfinder/userfiles/files/15410053466.pdfIn PDF document text
    • http://jr.ac.th/ckfinder/userfiles/files/kikojudizetaxepojuraxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=carrier+oils+for+aromatherapy+and+massage+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_off0000cfcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFCD 11088 bytes
SHA-256: 65633bbff4cfd9ad9a8e94cf278f171293459cf71a2bf896ac7508f1da212e2d
font_01_sfnt_off0000e942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE942 17592 bytes
SHA-256: 98cb889f88a2bea1a7fbf54e4f65525c3bdfebbc26d2c10535a7889ea216db45
font_02_sfnt_off000116cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1