Malicious PDF — malware analysis report

Static analysis result for SHA-256 275865e44e7e1b1d…

MALICIOUS

PDF

82.1 KB Created: 2021-09-13 19:11:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: aa9ab1e5cbe068ffb45a0420e6a21263 SHA-1: 7016cf7d9e01c3c9cb06c5bfb19d96b6c7b20ab6 SHA-256: 275865e44e7e1b1db27a395fd2d25e027a903c1764dd544159cd005b98d19b41
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains a link farm pointing to various domains, some of which are hosted on compromised CMS uploads, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the structure and URL patterns are consistent with malicious PDFs designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://dotacjedlaoze.pl/userfiles/file/98007312287.pdf In PDF document text
    • http://ps-chiptuning.hu/userfiles/files/38794511877.pdfIn PDF document text
    • http://pecsimutargygaleria.hu/files/file/zopelalitogewisidejosup.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/60702777139.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/73843791571.pdfIn PDF document text
    • https://savitravel.ro/ckfinder/userfiles/files/79297998473.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd48e322d5---zomamakovolajavodexewiko.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210901215237.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/xoregenolafa.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/1a83c65f94d1af6432e2ebeed98e48b5/65731704858.pdfIn PDF document text
    • http://studiocinti.eu/userfiles/files/36941330668.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/31146653068.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1630548374.pdfIn PDF document text
    • http://tnslib.net/userfiles/files/buzatala.pdfIn PDF document text
    • https://cometsecurity.in/admin/userfiles/file/99899079783.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/tametamigiwejuvamixa.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/76140118241.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/j1cjq2m2o1ct95b417btdrrhrb/goralizasum.pdfIn PDF document text
    • http://fundacionecla.org/resources/original/file/nizukigo.pdfIn PDF document text
    • https://wcfkenzi.com/ckfinder/userfiles/files/zotogodovawolotejupegu.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202192146141988.pdfIn PDF document text
    • http://eiffelflowersquesnel.com/userfiles/file/fatinevafemosar.pdfIn PDF document text
    • http://jn-zhsc.com/upload/69068394809.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=watch+the+walking+dead+season+11PDF 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_off0000de57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE57 10772 bytes
SHA-256: b704cc054b75e1479e692c47d8a51410391e1e73f7b9fb0ca9ee6358e3e0dee3
font_01_sfnt_off0000f704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF704 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F16 16852 bytes
SHA-256: 4362a43fbb4c581951e5b7f9cf36f2f01402831138d39c65a36657d11b50e76b