Malicious PDF — malware analysis report

Static analysis result for SHA-256 f13963058924daa2…

MALICIOUS

PDF

69.2 KB Created: 2021-09-16 18:46:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 836c4be42410b01be06c7b1d1566e7de SHA-1: 2b5fb2fffb0ce14642d5f239b003b12c7b5c11ce SHA-256: f13963058924daa2a5fb93a29ee36771cc9c588f6260d9268a9047ffa0234a88
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF exhibits characteristics of a phishing lure, including being image-only with a click-outward action and a small file size. It contains numerous external URIs, many of which appear to be part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://infrive.ru/uplcv?utm_term=rocko+the+pebble+and+the+penguin PDF link annotation
    • http://aquaclub.hu/userfiles/file/93800518204.pdfIn PDF document text
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/18147289661.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/90866590744.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/66287966074.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-5/20210905100133316219.pdfIn PDF document text
    • https://trainova.com/userfiles/file/71971794957.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/13975657615.pdfIn PDF document text
    • http://lex.tj/img/file/wibovajebokezijo.pdfIn PDF document text
    • http://theponghop.com/upload/files/rojebupupaxa.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/61429352551.pdfIn PDF document text
    • http://sheilahancock.net/blogfck/file/loperefugimokek.pdfIn PDF document text
    • http://dentistturkey.com/image/files/65379257956.pdfIn PDF document text
    • https://gadesign52.com/uploads/files/202109021657032825.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/roduzaboganajibikabi.pdfIn PDF document text
    • http://dentish.ru/ckfinder/userfiles/files/pofidazejitu.pdfIn PDF document text
    • https://sananselmo.com/wysiwygfiles/file/31175314846.pdfIn PDF document text
    • http://thegioioto.store/upload/files/58150995010.pdfIn PDF document text
    • http://globalbando.com/DATA/upload/files/202109161626098782.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614018bf7e969---6158776541.pdfIn PDF document text
    • http://djapm.com/userfiles/file/3002479571.pdfIn PDF document text
    • https://cmf8.ir/data/file/bunevixupidekixuwitasor.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379ec631d5f---92119291249.pdfIn PDF document text
    • https://hoanghaie.com/Images_upload/files/34474089180.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/wonunotugatuxajat.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_off0000b31b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB31B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB32 10904 bytes
SHA-256: 776f2caa35489ec6937ea1572f1a5e56fc0d33f119b0e1b197edbe1b3b64ed9d
font_02_sfnt_off0000e3ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3EA 14108 bytes
SHA-256: eb78e9a35c3214477dc13809fef9ef00c303ad34fad5e243bed00e45abd34f63