Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2a5d71082e948e5…

MALICIOUS

PDF

80.4 KB Created: 2021-09-19 19:51:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6806d19037345a04a5d146a5f30a20fd SHA-1: 7a33d3624511f457fab1555a70b7cdc132956ec9 SHA-256: b2a5d71082e948e5f91f906c1193817b70057b66a6579a85c3a640b726bbeeca
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farm heuristics, indicating it is designed to redirect users to potentially malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://krisoc.ru/uplcv?utm_term=bmw+golf+playoff PDF link annotation
    • https://holycrosshealthcare.com/userfiles/files/safazejalufe.pdfIn PDF document text
    • http://adgroup.co/userfiles/file/14748262822.pdfIn PDF document text
    • https://onlinendttraining.net/files/juzezakurulu.pdfIn PDF document text
    • http://onlinetalk.jp/app/webroot/img/fckfiles/file/44039089803.pdfIn PDF document text
    • http://uniondrygoods.com/fckeditor/userfiles/file/widadotubewelatuduwok.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/45993422860.pdfIn PDF document text
    • http://bartuceviri.com/userfiles/file/filenaduva.pdfIn PDF document text
    • http://instalater-macecek.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/jelagemo.pdfIn PDF document text
    • http://cke.hk/userfiles/80155757738.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/xosox.pdfIn PDF document text
    • http://riggi.ru/userfiles/file/89953936271.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/10839049909.pdfIn PDF document text
    • https://dalilak1.com/userfiles/file/busexixowotilibu.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d74779a404---dafobifivetezuvegodiruk.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/boxolitomaxojarimukidaguv.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161412e5781d12---67123352980.pdfIn PDF document text
    • http://metabolitplus.ru/files/file/zerun.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/71550362455.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613b9a72d9b39---xelaxup.pdfIn PDF document text
    • https://edgecs.com/documents/vadipame.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/161455e9ea059f---80924050094.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_off0000d59f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59F 10260 bytes
SHA-256: 8e1cdc64a95e85a0915aac3dbd51d4ea712406fca2a076f2c4e4fc0094cd9961
font_01_sfnt_off0000ecd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E3 18292 bytes
SHA-256: e892cc96bba3616ec7c906365a351806ac8ee67ab1f5f9395af2f9c77ad60003