Malicious PDF — malware analysis report

Static analysis result for SHA-256 140a9df20343b5c7…

MALICIOUS

PDF

75.1 KB Created: 2021-08-21 16:28:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 027193ee5da64f4c0d0a279938379f5c SHA-1: 0a494f1a62dd6bbee4f0d8b27ed9545b79fbc6bd SHA-256: 140a9df20343b5c70cf3b254d2945edfb290ad61ed2a3646aaf65f42b724ec99
124 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan. Static analysis revealed multiple heuristics indicating it functions as a link farm, directing users to various external PDF files hosted on potentially compromised or disposable domains. The presence of numerous URLs, many with UTM parameters, suggests an attempt to track user clicks and distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier clean score 0.1256

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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
  • 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://huntic.ru/uplcv?utm_term=volume+of+3d+shapes+worksheet+gcse+pdf PDF link annotation
    • https://purevdavaa.mn/uploads/ckfinder/files/6383712968.pdfIn PDF document text
    • http://clingac.com/d/files/kirotenoferivunakube.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/2106fmepgk70fr9jr12pm1c3lp/pikarusavawejesavukag.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083a0bddfc6c---38647915343.pdfIn PDF document text
    • http://farmaciafici.com/userfiles/files/bemotaxuvujenagug.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/rolerexedosadinemalo.pdfIn PDF document text
    • http://heatherjansch.com/ckfinder/userfiles/files/32153317338.pdfIn PDF document text
    • http://digitalpolicycouncil.com/imagenes/file/99532590483.pdfIn PDF document text
    • https://oriontradecom.com/ckfinder/userfiles/files/53529357927.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/lutunux.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609544545a3c3---wubopegulupesumifam.pdfIn PDF document text
    • http://www.udelimpa.es/ckfinder/userfiles/files/3724795273.pdfIn PDF document text
    • http://makinsushi.com/uploads/files/51731928009.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/tujewo.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/8493769726.pdfIn PDF document text
    • http://musiconthebay.org/clients/2/26/269dd5bc96e197da989a8dccc71442af/File/nelafawowiwudipakabovixu.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/570985974aaf98c9eef24a94089c6fe9/vibawobonalumoxete.pdfIn PDF document text
    • https://icon-studios.com/userfiles/file/27517290320.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-7-6/20210706195259973486.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16110b3ea46476---37749334701.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/96030a742df9fe9832c21f1b0650bbf4/rawudulawesop.pdfIn PDF document text
    • http://chapelguild.com/images/usr/79074504397.pdfIn PDF document text
    • https://www.nevjegykiraly.hu/userfiles/files/97520230916.pdfIn PDF document text
    • https://doxity.ro/ckfinder/userfiles/files/salebutit.pdfIn 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_off0000c880.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC880 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE092 16908 bytes
SHA-256: a89d7e9d9ccd602cdf50da64f161aed216ccc0cbae469deabb4d519f4b176726
font_02_sfnt_off00010d14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D14 11288 bytes
SHA-256: dc92502996fe6c3332f381373b4c85255d2ee941cb952967dadf6472d9936cf3