Malicious PDF — malware analysis report

Static analysis result for SHA-256 91b720f527708a60…

MALICIOUS

PDF

92.2 KB Created: 2021-09-02 11:34:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 0c20f727d8b87e9ab3fc661f18c962d8 SHA-1: dfc67955405faaaad84fff1aa9d28c1f83c31c30 SHA-256: 91b720f527708a607591493878d2bb3f3254a891757cebd1b0a4e5d07551fa0d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://alimentosldm.com/userfiles/file/mikomolosowebarovusuviga.pdf In PDF document text
    • https://sportsslife.net/upload/ckfinder/files/zisaviwo.pdfIn PDF document text
    • http://vetsnab32.ru/userfiles/file/68405176337.pdfIn PDF document text
    • http://royalwedding.jp/images/blog//file/64902345393.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/jasutux.pdfIn PDF document text
    • http://longthinhphat.net/uploads/files/dotuxokizobuxegowiw.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/bagilamarivarav.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/82759189330.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/817925a3f26fa3dca20fd4a3bc15eba1/lazufokafodine.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/59249674983.pdfIn PDF document text
    • https://mm-podium.ro/userfiles/file/lusafefugaloj.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf1243be05---luvopemoxokisuxigajekebuv.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/58462053118.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/r9jmjg0k39b3dhrnbaf0msntn2/81297256149.pdfIn PDF document text
    • http://europavloeren.nl/siteimages/file/98166451642.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/lazajesemajefijipuzowizok.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/12198774169.pdfIn PDF document text
    • https://badrivishal.com/media/43114596467.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/supuvinewivefo.pdfIn PDF document text
    • http://prodottoitalia.eu/userfiles/files/valisepakonofepamupuvuve.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/siwafovelakav.pdfIn PDF document text
    • http://wamer.org/userfiles/file/riwefezuled.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=la+guerra+de+los+mundos+orson+welles+libro+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_off0000fcd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD1 20096 bytes
SHA-256: 035e1f87125232c97c63e1b2eec34cd42654fb6e5ce6e884b550ef59b08adbc2
font_01_sfnt_off00012ff4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FF4 11024 bytes
SHA-256: 23638be5dac68c7a41c151a4a751d807e75d70f33cdb72c7b96ea72e0fde5f20
font_02_sfnt_off00014926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14926 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1