Malicious PDF — malware analysis report

Static analysis result for SHA-256 a57dd9718f87d9cc…

MALICIOUS

PDF

73.9 KB Created: 2021-05-16 00:52:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: e228084da6767bf038d86c410beabba9 SHA-1: bf6d6d4aa07ef21f8d85aff7aefb1f7341c43f9b SHA-256: a57dd9718f87d9cc8495dca74a0335ddd9bf78db1fa7aea2d250af38d75c6d59
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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 0.9998

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://stark-tools.ru/images/uploaded/rasejan.pdf In PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/puk19e14aqtthq59idrmj7urj4/mixenasowubu.pdfIn PDF document text
    • http://aplus.to/userfiles/file/goxerob.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/peq4c94758f35354dioef96nv0/29755690614.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/duwokimovajujegebuxeju.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9ca451847---razadavi.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/6330501e9c76f7bab88a4c4d0c1d403b/69948475402.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/nasefojuvevavaduborebi.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160760aac451e8---40542087695.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210514194602.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/c59161f7f2d59f46548ddbaf2e70be77/nabofurupa.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608113b9e7c76---lujerudoniselutob.pdfIn PDF document text
    • http://aliglobshop.com/userfiles/file/felukopo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a9237731ad---93786836521.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607e3c4143c13---82249285254.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=rch+melbourne+guidelines+bronchiolitisPDF 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://scripts.sil.org/OFLIn 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_off0000d112.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD112 5288 bytes
SHA-256: 76d7bf0a8487397f1d03712b85777c5abee24e0e979742b788430aba715bdbcf
font_01_sfnt_off0000e2e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E5 10104 bytes
SHA-256: af91bc259903bda3672fba2c811aa8ef7f8248a1bc21e365e1a984c4bd366ad4
font_02_sfnt_off000105ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AE 16060 bytes
SHA-256: 4ef9506ee11a349461550e6b437e3786686b598308a87786035880d16624999d