Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb56cd04c284b8ca…

MALICIOUS

PDF

92.0 KB Created: 2021-07-22 08:20:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 75c73af2ca542e54ad76a7ddcd95bf8e SHA-1: 86054cdc5b2df784e3934cb29bf28ee9613da040 SHA-256: bb56cd04c284b8caf416d77b02f4f6f59f01b7fcea276b3b90895edfed4f2ff3
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristic analysis revealed that the document functions as a link farm, directing users to multiple compromised WordPress upload storage locations and other disposable hosting sites. This pattern suggests an attempt to distribute malware or conduct phishing attacks by leveraging numerous external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://chupanhnoithat.vn/upload/files/dufatuxovotatovawezujivef.pdf In PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/zizobikikagogud.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/5c528117078244ed3f8a9f1c347d9ffa/bigafatafuw.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/mipupejerotajuwodubenuxa.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/q33t6vm602vqoeanjkn4ehmch1/jobokipujulef.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160766632cd6e6---91989012005.pdfIn PDF document text
    • http://jongauger.com/ckfinder/userfiles/files/91138628824.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/musatatirunelokes.pdfIn PDF document text
    • http://seritour.com/rsm/files/74667573553.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/d0a6fa3e10cb9644c4656d8269bc9ef3/xinelulerukosexanol.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/11b0a78ece3a8c8541d7b18ccbd99066/26029270876.pdfIn PDF document text
    • http://balone.net/_upload/file///30947441347.pdfIn PDF document text
    • http://orhs89reunion.com/clients/77823/File/84880274011.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/vunuvuzavowenibim.pdfIn PDF document text
    • http://branpc.in/ckfinder/userfiles/files/64583926272.pdfIn PDF document text
    • http://kbchina.de/upload/70936596707.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160810e430576a---nuwesunilomon.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c2094ca5a---57730196173.pdfIn PDF document text
    • https://agrimal.pl/userfiles/file/36723870565.pdfIn PDF document text
    • https://datajournonepal.org/files/56788924678.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c02a5aa514a---gexam.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1608a845b65537---25806771911.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/lewujusoxigomudumiwadugu.pdfIn PDF document text
    • http://yjsyrj.com/userfiles/file/jokisezofu.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ac2c654bc---kakimixezal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=it+only+takes+a+little+faith+to+move+a+mountainPDF 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_off0001025c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1025C 10704 bytes
SHA-256: bb2d463eb6df784f0db3b04c1f9aa0dc81d203ff1cce97c6ec76b7e7fdb0280c
font_01_sfnt_off00011ace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ACE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000132e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132E0 17316 bytes
SHA-256: a9815ee86ed475008aae0488b1881eb67b5ff27ecfd263f5a046ae6838053221