Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b2f3bc76f6c5a01…

MALICIOUS

PDF

71.4 KB Created: 2021-10-02 11:36:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6dbbbf2773f7f2df4dc65e1f34c1bbee SHA-1: a85cb0ee0779f71db948c3b5473e9aa0d2696bd1 SHA-256: 7b2f3bc76f6c5a01fb2e49d2cb5f36e75d887aec3f496ef84cc9813ea69070eb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The numerous external URIs, many pointing to compromised CMS upload directories, indicate a link farm designed to redirect users to potentially malicious content. ClamAV detection and ML classification strongly suggest malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=what+is+the+square+root+of+4608 PDF link annotation
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/bc92eb789a2d2ec48f951b2b720dedb4/67592516931.pdfIn PDF document text
    • https://arerp.kr/data/file///44581565289.pdfIn PDF document text
    • https://riosemarescentrodemergulho.com/ckfinder/files/33739716472.pdfIn PDF document text
    • http://newgatedesign.com/Images_upload/files/wolilib.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614da943c0b38---59986407582.pdfIn PDF document text
    • http://alituncer.net/userfiles/file/ririkugurinevigop.pdfIn PDF document text
    • http://taispacedesign.com/upload/files/niwanan.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/gibuzidigog.pdfIn PDF document text
    • https://www.shipgo17.com/plugin/ckeditor/ckfinder/userfiles/files/48873956665.pdfIn PDF document text
    • http://resheto.ru/users_images/fck/file/24405446666.pdfIn PDF document text
    • http://hanasushipickup.com/uploads/files/sivojelisoxax.pdfIn PDF document text
    • http://car-zone.sk/data/data/file/pafaramalibefagajejubupif.pdfIn PDF document text
    • https://pcetravel.com/files/file/52829105632.pdfIn PDF document text
    • http://sasmedm.com/www/js/ckfinder/userfiles/files/jitud.pdfIn PDF document text
    • https://zlatartopalovic.rs/files/sopetoxan.pdfIn PDF document text
    • http://downtowncincyhotels.com/core_degree/admin/images/cms_imagesfiles/tapepufujitusanupodefuni.pdfIn PDF document text
    • https://www.whoamiandwhyamihere.com/ckfinder/userfiles/files/33525352560.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/zititafakuj.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/a4286a18684812f24197f1a912da9cd8/61154096959.pdfIn PDF document text
    • https://micro-logic.ro/images/uploaded/file/65729224579.pdfIn PDF document text
    • https://remont-bez-zabot.ru/files/file/wotijerelirabe.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_off0000b1b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1B3 10976 bytes
SHA-256: 48b8df59eb5d6e933b7f7d3b28bbeb80cad3903ebd7d1b86e0ab1d5c87310f3d
font_01_sfnt_off0000cb69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB69 17632 bytes
SHA-256: 0c202f10f926670c209ab0af244d0c89177f4d55207e4e7fd6a29ee9fa8b3764
font_02_sfnt_off0000f7bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1