Malicious PDF — malware analysis report

Static analysis result for SHA-256 836ae8906028e1b3…

MALICIOUS

PDF

68.2 KB Created: 2021-10-02 21:46:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b2f261ddd246e4ca7b85cc851a792c79 SHA-1: c7b0d06a360b729a6efa66d5967409ba51a4fce6 SHA-256: 836ae8906028e1b3fa77308b26b8dc20e64a4274424bb34f176044a3428faffa
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a phishing lure due to its small size and image-heavy content, typical of a screenshot designed to hide clickable elements. Multiple heuristics indicate it functions as a link farm, directing users to various external PDF files hosted on potentially disposable domains. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest an intent to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 68 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 http://acudrved.com/ckfinder/userfiles/files/69236398839.pdf In PDF document text
    • http://exhibitionchannel.com/upload/4471909253.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/94d2443144018f76f3a0bbff4de49c4e/95110857547.pdfIn PDF document text
    • http://airmon.hu/images/files/suzebuduguxusewekekogu.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/56014803656.pdfIn PDF document text
    • http://www.bc-arman.kz/ckfinder/userfiles/files/vodazegijolef.pdfIn PDF document text
    • http://ltpbetel.ro/userfiles/file/77477445429.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/torop.pdfIn PDF document text
    • http://ericshartman.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/14328527614.pdfIn PDF document text
    • http://ulv-fogger.es/d/files/93785141344.pdfIn PDF document text
    • https://tennis94.fr/img/pics/files/zukefinevad.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/jawokuvedorelam.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/jifupa.pdfIn PDF document text
    • http://promenade-perpignan.com/userfiles/file/digutok.pdfIn PDF document text
    • http://vikingpaint.com/user_file/file/gedurube.pdfIn PDF document text
    • http://worldprint.su/userfiles/file/kalenab.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/43690379215.pdfIn PDF document text
    • http://yearbookplus.com/uploads/ckfinder/files/fazuwogunevegegig.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/48106987274.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/xodagifabe.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/161317f4bcb907---796810357.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/kubolefokof.pdfIn PDF document text
    • https://ripedesign.com/app/webroot/files/fckeditor/file/65814890778.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=are+sharks+omnivores+or+carnivoresPDF 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_off0000aff4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFF4 10488 bytes
SHA-256: 883d8f7c57a6a96be784994fa95d34013e684ad0e1bf830e9a67a462524d26a2
font_01_sfnt_off0000c7ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7AC 14160 bytes
SHA-256: 36164a65af1f7ecd6d69a783d48fa6dcfd68132038a85e1edc5257afce1b80bc
font_02_sfnt_off0000eb17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB17 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1