Malicious PDF — malware analysis report

Static analysis result for SHA-256 a188ef78a40b2a2a…

MALICIOUS

PDF

91.1 KB Created: 2021-07-02 20:56:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 51ed12c295fd6e020af5723ac57facea SHA-1: b57738c7d1161444b2aba7318a1b764ff6ed6d61 SHA-256: a188ef78a40b2a2a2df487837a70738f09dfb2619638ebe8bd3c33fa86da6c98
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious content. The heuristics 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest the document functions as a link farm, directing users to potentially compromised or disposable hosting sites. The presence of numerous unknown URLs further supports this, indicating an attempt to distribute malicious content or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://azizolace.cz/images/file/sexuzigafe.pdf In PDF document text
    • http://udmvdpo.ru/images/files/bobun.pdfIn PDF document text
    • http://alimentosldm.com/userfiles/file/sewukotokesuzemisofaludop.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd64d9d8e0---fijuraravizipaxijiwetit.pdfIn PDF document text
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/670pqmd0ik6361atr6vj4kh80q/pazakebekem.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/lbt6td73hgsmfh0f9f1ura1rvn/ragop.pdfIn PDF document text
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/5b44e3919020f38048d1006a9043d918/fomifapuzo.pdfIn PDF document text
    • http://suamayin.biz/userfiles/file/loxolokikapajilinobop.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608af695ecd0c---nomunijaxuwo.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/a6e93a5bc87714ab797fcd3ec7599bb0/jemapodipusaxujosuj.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc65e171389---99062124017.pdfIn PDF document text
    • https://bursac.net/userfiles/file/laloxupogo.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/pifajolejenedobijuro.pdfIn PDF document text
    • https://ols.lighting/wp-content/plugins/super-forms/uploads/php/files/30cfd210a4b9ae1aea322778470643b7/pezegunimozedajibojaje.pdfIn PDF document text
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/47da909f9916d80bc670bd919665bf85/tilopanifujomu.pdfIn PDF document text
    • https://promise-land.com/upload/file/51924140873.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/hno44afcobumfosms1t7ntf4s6/69456948910.pdfIn PDF document text
    • http://sushiosushi.com/uploads/files/damusisuvegogo.pdfIn PDF document text
    • https://hgb.se/filer/file/zegudimipinamuwumonexet.pdfIn PDF document text
    • http://teplolux72.ru/upload/file/bupiwaxu.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609478ff81d0e---lapadekekuwojujobevorela.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841e3db060c---69573168791.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fbe7453ea---46605777196.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/27e6417ed74dbbc405a96480613a2764/54383793880.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/f7c4e27f5b73b9fccf24c96efe3bf1ca/36749637923.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/pubokovupuvibibujuke.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=definition+of+upward+mobilityPDF 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_off0000fe3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011653.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11653 10932 bytes
SHA-256: ad52a29120c0a83e5ff34029b94e3f03a1dbf8cacc7f983996985ef3e2b8e45c
font_02_sfnt_off00012f71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F71 18028 bytes
SHA-256: a176a63a98f74762a278de786add169295db0d071c21014c016e628573aa98a5