Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b90fec1a534d961…

MALICIOUS

PDF

71.4 KB Created: 2021-09-07 07:14:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e034e05c0cb27bfbf0d09a03c0ea9b82 SHA-1: 98ec3f8a69841ca387498dc9da52201f9c01c2b5 SHA-256: 6b90fec1a534d961d299d528a1762e9057480c2b6e1de8725eadf83ae5c54483
156 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised WordPress sites. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous external links suggests a redirection or phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4abeee282---sakeneweridib.pdf In PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e40b98ccee---79653477758.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/958dl6pjp5mb2bsk44gu3525g0/75951551897.pdfIn PDF document text
    • http://burelomdo.com/ckfinder/userfiles/files/dofinigaronaxevunavox.pdfIn PDF document text
    • http://truhlarstvisollner.cz/data/file/gagewow.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/6757e78f0df4b2fe9d2457735991ccc2/35475403876.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/xitor.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16078be6cbccc5---metigad.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/7156408738.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/vawelakimoxuwoz.pdfIn PDF document text
    • http://jp-cable.com/d/files/fadukovebisosu.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16118317e39bdd---33209713041.pdfIn PDF document text
    • https://ms02bet.net/contents//files/76130361862.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/67023130716.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1406fb4012---fupafi.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/27205485056.pdfIn PDF document text
    • https://wittnebel.dk/file/kunafe.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611b4cad05735---kutigetesibud.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/49a036940627121d588afda2305879de/78628980283.pdfIn PDF document text
    • http://kme-kme.cz/files/file/jiluxovadivegoxulugebat.pdfIn PDF document text
    • http://pelesiuvalymas.lt/i/File/81219895621.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/07b2a7c8463718b23172c3ab3c4ee5b3/revugopizazavewol.pdfIn PDF document text
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1607aab852c396---60829779825.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/mavuxemobekonadugive.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/3d3gt0juedf2ph5e15a6912os1/nomanonasawoxum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=differentiate+between+prokaryotic+and+eukaryotic+cells+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_off0000b8bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d0d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D6 11144 bytes
SHA-256: 6c6761b436dbf2cf9428a40468a5c99ec8b980815887857a11b9b62b56a8c3a2
font_02_sfnt_off0000eae2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE2 14632 bytes
SHA-256: d415a6c82ba05c22911162877534551308e21c43fccb017e801d85689cb62fe5