Malicious PDF — malware analysis report

Static analysis result for SHA-256 37ed6a4758d15977…

MALICIOUS

PDF

71.0 KB Created: 2021-09-18 21:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 85906b8a650b54b851c4e1e1261161a9 SHA-1: d8e9419fd3ed83a82b03a43fedf6162f98f3991d SHA-256: 37ed6a4758d1597707ea380fc2fec7076af5034365c3a8bd29e006463b77e4a9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to various disposable hosting sites, a common tactic for phishing and malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or delivering a secondary payload. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirm the document's purpose is to direct users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://technology-mp.it/userfiles/files/20232693065.pdf In PDF document text
    • https://xn--fiqa735be48e.com/upload/files/61312899074.pdfIn PDF document text
    • http://cautrucpalang.vn/webroot/img/files/nosaforanonesovivogulum.pdfIn PDF document text
    • https://linker.tw/files/jexetulalazatos.pdfIn PDF document text
    • http://selmanoglusigorta.com/userfiles/file/17661076431.pdfIn PDF document text
    • http://hiredriver.com/uploads/assets/files/lowasunerubidiwe.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/ce95a47a0af9ea1d4921363e372d4779/37336486626.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613b278dc8b34---ludamawolekegowetub.pdfIn PDF document text
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/fepudibosanu.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/11897160774.pdfIn PDF document text
    • http://hpworld.hu/data/pic/Image/file/90611748791.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/sijusevoxi.pdfIn PDF document text
    • https://vibingvibes.com/userfiles/files/zonatidotame.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/kedodizurumusoku.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/bitikizik.pdfIn PDF document text
    • http://chandravanshi.com/userfiles/file/76596330882.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/1e982ebc417e0205c978f4a453786a58/68336076583.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613792877277c---bopabo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=download+4g+app+for+androidPDF 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_off0000b467.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB467 16704 bytes
SHA-256: a7e03fa10fedd970ab5427c48bf60064b7177826322f11df0360e37b235437f1
font_01_sfnt_off0000ded7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6EE 10440 bytes
SHA-256: 9986e29389abfc7369581f8ff4d07e94f6e7fc0e6109c1bf651d7f28f8b5e2e6