Malicious PDF — malware analysis report

Static analysis result for SHA-256 9394c8f2553ffb1b…

MALICIOUS

PDF

160.6 KB Created: 2021-10-05 13:34:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 01af2f9cec09efd6c5e68ab7d9d80530 SHA-1: 3c7a26a45e46cebd3dd9572a117d792e9ae2d9c6 SHA-256: 9394c8f2553ffb1b01e4bf22280e367baa29ae9c25c8e1b7e1c5ea9b91790fc0
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm containing numerous external URIs, some pointing to compromised CMS uploads and disposable hosting. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose, which is likely to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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 http://divorce-difficile.fr/userfiles/file/39479711729.pdf In PDF document text
    • https://mlspoland.co/files/file/bunotelaladavorut.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614a1bac5661a---ralududetosigapoboxo.pdfIn PDF document text
    • http://aaz.sk/editor_uploads/files/58524694749.pdfIn PDF document text
    • http://nutrizionisti.eu/public/thread/risorse/file/ditogopapa.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/pagevetigewogixeni.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/27761940611.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613249495b305---sagiroxa.pdfIn PDF document text
    • http://rentaruedas.com/files/others/xedojakaxiputomujadado.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/nabivagupujipovofuda.pdfIn PDF document text
    • http://elitacasa.it/images/file/11026259577.pdfIn PDF document text
    • http://agisinfo.ru/uploads/content/files/xuromavufanojezufisuxu.pdfIn PDF document text
    • https://bdprescription.com/ci/userfiles/files/nafogajirez.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/berajo.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/gabokorejakiz.pdfIn PDF document text
    • http://nomorecpapmachine.com/userfiles/files/tadukurojubewitexek.pdfIn PDF document text
    • http://sevinctekstil.com/resimler/files/46887548301.pdfIn PDF document text
    • http://xn-----elcksuhhemsi4e.xn--p1ai/files/files/divope.pdfIn PDF document text
    • http://futsalcb.cz/picture/vtextu/file/kepewewitaxarobelekevam.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16150fa0daa290---10647610924.pdfIn PDF document text
    • https://uzunlarpeynir.com/dursun/upload/files/87452561897.pdfIn PDF document text
    • http://www.atccs3.it/atccs3/fckeditor/editor/ckfinder/userfiles/files/jejisafavojud.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/71559339095.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=harry+potter+and+the+chamber+of+secrets+full+movie+hungamaPDF 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_off000207ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x207CE 11476 bytes
SHA-256: 75a02ffdeabcbe3f3a9eefa975daf4cf7bd0dc0f300b28f4c8eae49f3eecd0de
font_01_sfnt_off00022248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x22248 22272 bytes
SHA-256: e6eb0614781ca8caa071925c7bfde812af0aeaabaf348b28e07e6ed1009c7426
font_02_sfnt_off00025bea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25BEA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1