Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab4a8b24c9bb0413…

MALICIOUS

PDF

73.0 KB Created: 2021-09-23 22:55:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: fd9957b9a45b455e0fcf520d28cc14b4 SHA-1: 114ae01203c5e3aaf6650725094cb39534bab609 SHA-256: ab4a8b24c9bb0413b7cae3111b167382883e1726703c2a72a67221c5a602a09a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics suggests a coordinated effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://nomylo.ru/uplcv?utm_term=top+5+mobile+games+in+the+world PDF link annotation
    • http://boilerservis.ru/uploads/files/37904371813.pdfIn PDF document text
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/12020575763.pdfIn PDF document text
    • https://sibois.eu/userfiles/file/pufinibakizolaxofujapoku.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d167285830---19085282781.pdfIn PDF document text
    • http://ginzaramen.us/uploads/files/jubuzexivugokon.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/zugezudokafepugurovumeni.pdfIn PDF document text
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/93473908443.pdfIn PDF document text
    • http://labellebeaute.com.hk/ckfinder/userfiles/files/98279531212.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/mekuroji.pdfIn PDF document text
    • https://mi-stores.com/basketballtotaal/images/editor/file/89026725627.pdfIn PDF document text
    • https://taksis.lv/taksis/userfiles/file/12316630436.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614449115b7c5---32061176354.pdfIn PDF document text
    • http://eclickapps.in/userfiles/files/kojelezositobi.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301cab06a83---39567646880.pdfIn PDF document text
    • http://ros.by/ckfinder/userfiles/files/71782118020.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/jadelewelefikeguje.pdfIn PDF document text
    • http://babywagen24.de/userfiles/file/xutijexegidilivigilidovus.pdfIn PDF document text
    • https://thuhuonglacquer.com/uploads/news_file/47021920092.pdfIn PDF document text
    • http://zjleiou.com/images/upload/File/37617136420.pdfIn PDF document text
    • http://yilbasipromosyonu.com/userfiles/file/91374143289.pdfIn PDF document text
    • https://fleseriuassociates.ro/files/file/duwunog.pdfIn PDF document text
    • 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_off0000b8e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8E5 16952 bytes
SHA-256: d452b797378a38685c52b7a05af16acb68d0e5d0a5ce056ff2d36a9513ddcc3d
font_01_sfnt_off0000e538.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE538 11164 bytes
SHA-256: a330e314b16ce317af1818f55cc8c6c8c294ac71632c337873036b89fb1bd61f
font_02_sfnt_off0000fec2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1