Malicious PDF — malware analysis report

Static analysis result for SHA-256 b20a7d1d2adb5070…

MALICIOUS

PDF

72.4 KB Created: 2021-09-30 10:34:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 931c2498c85ed801208ec1b62bbed2e0 SHA-1: b6539d671ebcc36e21ada3d1fa2c1e66b09c71d2 SHA-256: b20a7d1d2adb507016ed49729c068da5f788df6c3910f6aa9f3533e98d29dead
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to various unknown PDF files hosted on potentially compromised or disposable domains. The presence of numerous external links, many pointing to PDF files, suggests an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • 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.
  • 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://abwalabamaave.com/uploads/files/xajud.pdf In PDF document text
    • http://krukewittfarms.com/userfiles/file/52353977812.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/95e7a52ec102689f67de958130aabb51/bemevik.pdfIn PDF document text
    • http://naturenhuman.com/app/webroot/userfiles/file/xapifojitotiviwazulanedo.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/misemowoza.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/49f5724bf514fe814eb27036d31a72b3/nupififadile.pdfIn PDF document text
    • http://madiran-cruduparadis.fr/ckfinder/userfiles/files/kumizoni.pdfIn PDF document text
    • http://obchodsezlatem.cz/upload/files/xejuwefenukajoruzeviwubeb.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/sobajoku.pdfIn PDF document text
    • http://artpolinakuzina.ru/pict/file/28911777532.pdfIn PDF document text
    • https://chungangroup.com/uploads/files/202109072203028153.pdfIn PDF document text
    • http://drtamerturan.com/file/wutakoxunavonub.pdfIn PDF document text
    • http://messtores.ca/fck_user_files/file/sevabizenato.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/xifakamawotuj.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/72223126154.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/38751413038.pdfIn PDF document text
    • https://tourpon.kr/FileData/ckfinder/files/20210924_90A8DB242975E889.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/vejolabuwivegabemus.pdfIn PDF document text
    • https://plewmal-d.com/Uploads/files/fazimavuvu.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4b0e39d2b---41231368683.pdfIn PDF document text
    • https://mbbs.hr/files/sazolefofiwodipode.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161349a4e19a3d---95625542708.pdfIn PDF document text
    • http://katachizu.com/img/news/files/46083863883.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=graphics+programming+in+c+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_off0000b5e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cdf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDF2 17588 bytes
SHA-256: a5bf482a00d7067c092f447ee89928534ea15f8dee488f65aa90231e082cad5f
font_02_sfnt_off0000fb40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB40 10832 bytes
SHA-256: 4170d3a4d31ea03ee5cf9bdc175528939c1706f30e22b69f5c698d48b1c15f35