Malicious PDF — malware analysis report

Static analysis result for SHA-256 85d4a2f9a5d9f209…

MALICIOUS

PDF

60.6 KB Created: 2021-06-23 22:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 1269bae0dcaa9388d1a0c2e8f695c936 SHA-1: aea53a3b07e10cb48c49f3b96a82f616d617bf38 SHA-256: 85d4a2f9a5d9f209fc8b7a69889a03353be339587ad8d035e2c6ac6e39090551
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to multiple domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting an attempt to distribute further malicious content. The document body, though partially corrupted, indicates a lure related to a 'free worksheet'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://magyaringatlanadatbazis.hu/dev/_user/file/josidupanuvivazodetuxuzor.pdf In PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a47bc99393c---2233322627.pdfIn PDF document text
    • https://burgas-remonti.com/userfiles/file/45413578928.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd360a552a---dagive.pdfIn PDF document text
    • http://rebornfair.com/FileData/ckfinder/files/20210621_7B8D0DB6E89EDBF3.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210430235330919372284.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/zevopevope.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/2ff899f1408c920bcdf190842b03a3d1/sadazibodejuxarige.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/63796206606.pdfIn PDF document text
    • https://sardavetri.it/userfiles/file/kiwikezuxasivewitatukage.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/49a582fb4572e1034a97c5c985da0c47/mizadimufakajuseluki.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16080e15931238---25439599522.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/7a60a8603be68628f2fa9d6e7e968293/makijez.pdfIn PDF document text
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805fc9c236f---rozumideter.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb7daaf026---32543417418.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/i3c75pq3ld06ncl08otl84mo85/47928144098.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/dokiduwitenawoxexuvafox.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=free+worksheet+for+lkgPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b377.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB377 4932 bytes
SHA-256: 47e7deaa84fb6312bc03063f17b987f5e104101d79c470f5a47e1e9af6613834
font_01_sfnt_off0000c454.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC454 9340 bytes
SHA-256: e42e4e11d703d5986856ba03f425668d403975ff06f00b0be2d98481dfd57698