Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4c38af88a03e7f1…

MALICIOUS

PDF

80.0 KB Created: 2021-09-16 08:19:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 727566c3715d7ae6e31d7445a0dbd96c SHA-1: ab20cb16b7d943e59af99f590a702689b4f02e57 SHA-256: b4c38af88a03e7f13d6ff850b253449da9f479a77c232eac504973794282bad7
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users to malicious content. The presence of these links suggests the primary goal is to facilitate phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://toppelletmachine.com/d/files/58322812106.pdf In PDF document text
    • http://zehanbiopharma.com/upload/files/fulixuzedobalawabikufir.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/riwugokozuj.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/zarutukugaludenez.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/19230288982.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/dc50f0d107dd2db5b39859ff00044726/sumenobuxonitadarujafolad.pdfIn PDF document text
    • http://jsdarvin.com/files/jikabiritiparogavirubek.pdfIn PDF document text
    • http://sh-songshi.com/admin/upimg/file///gezezijo.pdfIn PDF document text
    • https://virker-ikke.dk/files/pitus.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16138e4a10db80---73490082049.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/putevabelixesiluj.pdfIn PDF document text
    • http://maskaevlawyer.ru/userfiles/file/86563664068.pdfIn PDF document text
    • https://daquin-ferriere.fr/userfiles/file/lepusawijowuzo.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b7deb16e0---64119785965.pdfIn PDF document text
    • https://pellevah.com/upload/files/gitakujiwemabuxexobuxiti.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/13726369410.pdfIn PDF document text
    • https://ratoempat.com/contents/files/wekuxi.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1613e267a36db6---96527692853.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/043e24341260b3644393a5856324308a/83125583912.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1614229dbc6c5b---2579792025.pdfIn PDF document text
    • http://liily.jp/upload/file/20210906083051.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/luzud.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/kagidiwivodabef.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfccdbfb6c---jilabodomulizu.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/78730902135.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=vikram+tamil+movie+onlinePDF 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_off0000d7c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7C2 17188 bytes
SHA-256: ed1fa8e6800ae26b4b6772637e3fb9189a0dd46ff1a398451a909c2f2f60cc7f
font_01_sfnt_off000103ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CA 10228 bytes
SHA-256: a2174c4b63f5dc72cf28a0df4501db5f2edc50abaa36283fdc21e7e0ca38f464
font_02_sfnt_off00011abb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ABB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1