Malicious PDF — malware analysis report

Static analysis result for SHA-256 31d9ff605c6090c9…

MALICIOUS

PDF

121.4 KB Created: 2021-09-08 05:21:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: b0e2c8e21450db26ef6188839bd02399 SHA-1: 7bfdf5b9c38c4701c6976598f8784fd07567d1f0 SHA-256: 31d9ff605c6090c943bec9c9970d46e85868dc1eab1b709491499579f0767a93
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 0.9982

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://jvcc.cn/ckfinder/userfiles/files/2108180853003120669pojg.pdf In PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa29c67b419---rolirezematakuvifenaj.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087d1e010431---kafavumupobadudexedamuvow.pdfIn PDF document text
    • https://iva-vietnam.com/userfiles/file/75657915141.pdfIn PDF document text
    • http://amongelite.com/ci/userfiles/files/redezakevetikowewa.pdfIn PDF document text
    • http://petukmahaaaraj.com/userfiles/file/tudisazarazufesudija.pdfIn PDF document text
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/5d8530e777802622737db93bebe0e4ea/24581779350.pdfIn PDF document text
    • http://aviteksural.ru/admin/ckfinder/userfiles/files/50394795873.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/81e22a0fbddaaa21febeb5a160878c18/legokadisatevajatatad.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/sudelimupemoma.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210726232314.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbab8af61a---dedilituvoxazekolevavarev.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/tawivob.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/55e2ce06186a59730eadd60b734ca585/9391771290.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c5e4c8c13a8---gatidudusowupapulubekafa.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/43dbbedfe468985de665d5c0ca11ae8e/tupigoloxavamoma.pdfIn PDF document text
    • http://asfalon.com/__files/file/xetopovatu.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/4dl3ckhfq34bpe12m1scd0igvk/59823982376.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/hl6ptnq9oocsua4behpqs0k8u0/peritekeso.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/umlur6pha37o0q2dj3dcmuqvkn/26907528264.pdfIn PDF document text
    • https://tort-art.ru/userfiles/file/26920302764.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=plan+m%C3%A9tro+tramway+paris+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_off00016d93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D93 20960 bytes
SHA-256: 647b0755723d372dbbd46338c7cf906ce90c45c688943e0a721995738583d1bb
font_01_sfnt_off0001a497.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A497 10884 bytes
SHA-256: 03f4678ecc9c4340cbef31d2a0fa986b2b3be43ca05f3704199847f147c9bb2c
font_02_sfnt_off0001bdd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BDD0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1