Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac8f9a9c6f37cb52…

MALICIOUS

PDF

83.2 KB Created: 2021-09-13 11:49:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 81edb2e4700f560790023b14874b8885 SHA-1: cea0e2cd3c43642a063d090a1c75b70237d03556 SHA-256: ac8f9a9c6f37cb5226d725928f9fd6583e385ebb1e7bc9e232026aabab3eaeb5
156 Risk Score

Malware Insights

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

The file was detected as malicious by a ClamAV signature and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's used to redirect users to malicious sites. The embedded URLs, while some are marked benign, are part of a broader pattern of redirecting users, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://sbsoftware.ro/admin/userfiles/file/43253158755.pdf In PDF document text
    • http://telekommarketing.com/firme_data/files/38672129109.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/29006494222.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613150d83c1b5---gipiteluwoputobegiludaj.pdfIn PDF document text
    • http://dancephoto.ru/userfiles/files/72499561098.pdfIn PDF document text
    • http://www.pilartangguh.com/file/54654149577.pdfIn PDF document text
    • http://dekobonner.de/userfiles/file/gonajepet.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/22308208500.pdfIn PDF document text
    • https://golf-tout-terrain.com/publish/page/file/xuguxisukijemo.pdfIn PDF document text
    • https://eastmanllc.com/ckfinder/userfiles/files/torefu.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210903_095040.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/vuwugawonatotelaj.pdfIn PDF document text
    • https://inks.bg/userfiles/file/9208193310.pdfIn PDF document text
    • https://uslugiinzynierskie.com/eurostyl/photos/file/14389032917.pdfIn PDF document text
    • http://ngocphuocjsc.com/public/default/ckeditor/files/33715453425.pdfIn PDF document text
    • https://anandamsanyal.com/userfiles/file/23592041901.pdfIn PDF document text
    • http://huemin.com/fckeditor/userfiles/file/sigarij.pdfIn PDF document text
    • https://indolabtek.com/Uploads/userfiles/files/92971394438.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/batag.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135232810d10---58182075350.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/per65trngeo9d3ii6ihoh7thh6/fijidom.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/dajujudamepegazovukipidij.pdfIn PDF document text
    • http://ventilatoryzlin.cz/images/file/55175180039.pdfIn PDF document text
    • http://media-production.net/admin/ckfinder/userfiles/files/50250758478.pdfIn PDF document text
    • https://inprovitperu.com/ckfinder/userfiles/files/76088509459.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+export+mp4+to+mp3PDF 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_off0000de9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE9C 10268 bytes
SHA-256: e1475a7620434fccad1c65abfca8278dfcfbdeece5376e3e46e7aba80a7ae046
font_01_sfnt_off0000f5d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D0 19028 bytes
SHA-256: e5792e3d96b48d36401d177b3a19e01f3334c3ba0bc688d829a22f42dc1ebda2
font_02_sfnt_off000126dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.