Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b488115c50e293d…

MALICIOUS

PDF

75.3 KB Created: 2021-10-04 12:09:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1eb0ed00434a3febb49d7a0de1f1f6d3 SHA-1: 30b95a694046167872c5fd0ba495ec13069d51e3 SHA-256: 3b488115c50e293de6462bf652fe5ae76fef04677499320ff8f3652b8da0c7de
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, including one pointing to 'chcial.ru', suggests a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this by identifying the document as a link farm on disposable hosting, designed to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://chcial.ru/uplcv?utm_term=post+graduate+diploma+in+electrical+engineering PDF link annotation
    • http://koreabulk.net/userData/board/file/20170391484.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/a345858e99fc6a1d2faeab632ceb1ab9/74842622356.pdfIn PDF document text
    • https://maximaainfoways.com/WebExams/ckfinder/userfiles/images/files/61153610133.pdfIn PDF document text
    • http://tuclubcr.com/campannas/file/69105851330.pdfIn PDF document text
    • http://solo-reisen.com/media/images/file/56793213430.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/383fef5ba47a65fed208e75c44a23707/19983934500.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/rebumopusexubi.pdfIn PDF document text
    • http://anapharmata.hu/ckfinder/core/connector/php/files/tutegalirerev.pdfIn PDF document text
    • http://luisacortesearchitetto.it/userfiles/files/91566467317.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/mivipalenusawugosano.pdfIn PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/gozepugibewejefavaben.pdfIn PDF document text
    • https://juraganmonyet.com/contents/files/23302023807.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/53729372302.pdfIn PDF document text
    • http://tattooindex.nl/images/uploads/vufanodikirokonupe.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/42381593861.pdfIn PDF document text
    • http://strahyi.ru/images/file/37745782059.pdfIn PDF document text
    • https://topconta.ro/userfiles/file/18129926287.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/bamadirixalemusu.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/66996513811.pdfIn PDF document text
    • http://deborahmayerlawoffices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/timaxozenijanixob.pdfIn PDF document text
    • https://motodubai.com/uploaded_images/files/84887341743.pdfIn PDF document text
    • https://fibra-optica.ro/ckfinder/userfiles/files/lusizowilitet.pdfIn PDF document text
    • http://shortguycentral.com/ck_uploads/files/61001365472.pdfIn PDF document text
    • http://tc-antey.ru/uploads/files/semazuruzaximevobidofal.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_off0000c4c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4C1 16440 bytes
SHA-256: b888716df5b97343d30c3c9a09f0d5581e2d142d194e26f756c08b564937e0d1
font_01_sfnt_off0000ee47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE47 10960 bytes
SHA-256: 229689844053340e74547080354c7370602f8ff41ada721439128c55b501b487
font_02_sfnt_off00010785.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10785 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1