Malicious PDF — malware analysis report

Static analysis result for SHA-256 91de964f797c8913…

MALICIOUS

PDF

74.9 KB Created: 2021-07-22 15:19:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1635481ccec3ba6a54f8518a66b43af5 SHA-1: 9c4b84d2c581669a7071809054de72d150b8b990 SHA-256: 91de964f797c89139d0247435dcc3e2a5fc7b598e39160ba594be13cbce8dbe0
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://uceng.net/_UploadFile/Images/file/wirim.pdf In PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a4290873e4---jafarotaxade.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/ckvf4r4fci8i0fju9fesbb8k5s/49603656331.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b5e61c18e---lufamilazotewulineduza.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e7b7b4275b6---64841539887.pdfIn PDF document text
    • http://alexanderkanevskyartistbiography.com/clientMedia/file/82245000474.pdfIn PDF document text
    • https://soechi.net/userfiles/file/sukatigipolosolinubururi.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/il95fkn8br9otnk9fdtg7nna2h/88135733057.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607adc1be69dc---42985407007.pdfIn PDF document text
    • http://yuha.be/_files/file/gazewejotikadat.pdfIn PDF document text
    • http://camonetinternational.com/files/file/noluzepumetepabugano.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160867db96fd95---23284344853.pdfIn PDF document text
    • http://dallassymphonyleague.com/clients/1/14/14bb4a025281f1a32078cb68571f7cf3/File/mopadomudirolewadepeje.pdfIn PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608b691892dd3---84346959339.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c7615721e---55791434823.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160accea8a8fad---32827075310.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/umh64ri4ffdrcstqcf5hkddc04/juguwituridakudiv.pdfIn PDF document text
    • http://akicgiyim.com/userfiles/file/63514792047.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/gurikumomujomogonepula.pdfIn PDF document text
    • https://basisnomor.com/contents//files/pidavomulakeluvuvisozusi.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16089435572a17---bupuwojagigijojedosuput.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/1b6igboss39m933o8najdvvf4f/tuzir.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608723b525a6c---57567304066.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/3049b6236399b19d59c0fd6e0d44fb57/kunonuta.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=structural+approach+to+translation+book+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_off0000c1ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9FF 15948 bytes
SHA-256: c3571c644658f45d673e0bedef9cc09e9e106ec8decc74a05ad9eb621e671794
font_02_sfnt_off00010310.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10310 10992 bytes
SHA-256: 971f04b98da8ed264926557d1a8dd1c852dcd979923d647c6d216a70197e352a