Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0c7693f09dc1691…

MALICIOUS

PDF

68.8 KB Created: 2021-09-20 22:57:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 78aded6a5cc5b337465be0f6339db2c0 SHA-1: 9b9dc413eca8f95e93b9ca854b0ec8479f460f05 SHA-256: f0c7693f09dc1691f4a55ecbb7405dfc3c3219bfabef1289dd03fc6d3b18db5c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan-like behavior. It contains numerous external URIs and is structured as a link farm, with many URLs pointing to other PDF files. This suggests an attempt to distribute further malicious content or redirect users to phishing sites. The presence of multiple distinct hosts and the use of UTM parameters in one URL further support a phishing or content distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://inwebjor.ru/uplcv?utm_term=gta+vice+city+for+free+download+android PDF link annotation
    • https://egyiksem.hu/uploads/file/tipumigabolevifev.pdfIn PDF document text
    • http://2222.netsociality.com/upload/files/52956181965.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/47673764635.pdfIn PDF document text
    • http://boldino-hotel.com/ckfinder/userfiles/files/55825236502.pdfIn PDF document text
    • https://magatek.com/documents/file/42627834951.pdfIn PDF document text
    • http://maydemtienvn.com/upload/files/dakade.pdfIn PDF document text
    • https://gopherscopes.com/userfiles/file/35656147305.pdfIn PDF document text
    • http://drironcat.com/images/file/warumo.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/kaxifufebebamowagofodozu.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143d06aac9e5---6169910217.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/sozal.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/leniwavukebikumor.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/nanives.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/xasikumivoxevuwameruzowop.pdfIn PDF document text
    • https://digbijoynath.in/uploads/userfiles/files/vowikojuvatudaziv.pdfIn PDF document text
    • http://herfon-machinery.com/images/ckfinder/files/20210905225427.pdfIn PDF document text
    • https://tutorsbureau.net/userfiles/file/17191978911.pdfIn PDF document text
    • http://www.otevrenysklep.cz/ckfinder/userfiles/files/sitetogovonitoxu.pdfIn PDF document text
    • http://artiguardia.pl/userfiles/file/kikojumajonudubeninu.pdfIn PDF document text
    • https://khachsan295doson.vn/namthuan/images/news/files/70266978591.pdfIn PDF document text
    • https://digitaldaya.com/imagenes/file/48730366123.pdfIn PDF document text
    • http://unixsensor.com/uploads/files/202109051230026179.pdfIn PDF document text
    • https://tnmkor.com/FileData/ckfinder/files/20210903_9590AD53E8BF33C5.pdfIn PDF document text
    • 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_off0000af46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF46 10604 bytes
SHA-256: 606cbb3858c3ec58048a89c58c9824b92924c0bf045a6b84f71192d8629b9c19
font_01_sfnt_off0000c7bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dfce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFCE 14972 bytes
SHA-256: 73bba5a502b816a10efb38c2d6d6544da3b833d0d393ef0eaa5d9992124f540f