Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a3077171598eb10…

MALICIOUS

PDF

87.0 KB Created: 2021-07-12 16:30:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: efc3a26d61eecc17db028ab0e667cb24 SHA-1: e39acc3d445f870a7a769b5ab9934b0087b27b71 SHA-256: 6a3077171598eb10c21396d7331ab4b8e74e48d508079d634e0b5093f512a28a
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting it functions as a link farm to distribute malicious content. The embedded URLs and link farm structure strongly suggest an attempt to lure users to malicious sites, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://watertorens.nl/userfiles/file/lusovulubapexekeloluduma.pdf In PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8bb2c6c08---74170841019.pdfIn PDF document text
    • http://ouhkpthaa.org/userfiles/38787729493.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/fufelugome.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c859f29879e---vubixule.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/nolaxivemodavumudejitasu.pdfIn PDF document text
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607387b4ca471---wejuxuwuje.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/823le58pv7k2e0dfcj7fe14vd2/90230504871.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/19487121436.pdfIn PDF document text
    • http://goraku-sangyo.com/userfiles/file/5192569525.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5c62952105---direlodebi.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/kufiruwurekubafurufemepur.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/9d99081e8265acb63d4e76cbdaf55635/68949538386.pdfIn PDF document text
    • http://haus-st-otmar.ch/userfiles/files/xarumosakepesojoxa.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/9ofupnfr5fk2ra2ih33am0i0cl/nagikifivosazavu.pdfIn PDF document text
    • http://kimbuunguyen.com/uploads/userfiles/file/4828179500.pdfIn PDF document text
    • https://swift-tw.com/lcc/upload/files/47758592871.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca752cc4f6---44741687210.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/64021807429.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c392e938f8d---89697449709.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/95d961c000f0048b4e2e8880a8c843a0/majuxobefiwabiz.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c985c9c6db6---52194933504.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606dce6544edb---72686438880.pdfIn PDF document text
    • https://teenvolunteerhouston.org/wp-content/plugins/super-forms/uploads/php/files/f9d9187e8d970e3c40974d924ca56243/fawar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=synonym+thanks+toPDF 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_off0000f22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22B 17408 bytes
SHA-256: 92d37d3f4f175ac43408c7cc9c623fe1a5c0ff3e6caf9167f5757c3d32e26647
font_01_sfnt_off00011ff0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF0 10284 bytes
SHA-256: b2f06180bb20b2812e3b2e029f5b7bb52f000fe3a742834a9dfb5cb1085891b0
font_02_sfnt_off000136ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1