Malicious PDF — malware analysis report

Static analysis result for SHA-256 100c087d05ef3058…

MALICIOUS

PDF

83.5 KB Created: 2021-09-21 05:20:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 806174685df904bae765463f0fb91856 SHA-1: e4c8946bf85b7200cc5b2ce904256ac08a96fa41 SHA-256: 100c087d05ef305827a346113296b129d1d543b17cd866bd834a07582a841364
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a PDF link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. The document body is heavily obfuscated, preventing analysis of its direct content, but the presence of numerous external links strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/xegawudiliwaperusof.pdf In PDF document text
    • http://zae.me/datafiles/file/bomipavotinojoxuvu.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb25ba8489---74588947557.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396c5aeaa9c---89830437822.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/lenab.pdfIn PDF document text
    • https://nikolsbeauty.com/webroot/f/uploads/file/97540771708.pdfIn PDF document text
    • http://cycling-software.com/files/file/80411142950.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/vonagejuxotowo.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbea57976d---kelupizegavufomiwuj.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/e5c0c83ce805860b3fa21f7575f72b28/vagidiketamizilaxemova.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/keluvinasoporoleduwav.pdfIn PDF document text
    • http://donovaly-ubytovanie-safran.sk/web/userfiles/file/pogukolexuwolajemufipumi.pdfIn PDF document text
    • http://wdnederland.nl/file/dezefada.pdfIn PDF document text
    • http://miraesusan.com/ckupload/files/52015485619.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/7810161902.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/vomakebaledetagavelelax.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/todolopata.pdfIn PDF document text
    • https://salwangurugram.com/files/2178826963.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/f5037021d4ae99104f2d46b165ece992/405400427.pdfIn PDF document text
    • http://veterina-naslunci.cz/userfiles/file/sufogatodawuda.pdfIn PDF document text
    • http://mawratanews.com/armedia/uploads/files/fagokupixuru.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/zidakupaxunawomevafi.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/a433acfab87cade7353814add3bad947/wejasibupiw.pdfIn PDF document text
    • http://cesvil.it/filesUploads/file/gotaguxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=convert+ppp+to+pdfPDF 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_off0000e34e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE34E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB65 10120 bytes
SHA-256: b6265e78823f6be7cd503f651a52f768c2432b373322e7a57e6574b4ed172f3f
font_02_sfnt_off0001121e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1121E 17820 bytes
SHA-256: 1d724de057cd9be99b77f573e8331674def30b2080d5cea1a9e2d8715613e1c0