Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a403a15430b212a…

MALICIOUS

PDF

82.4 KB Created: 2021-06-14 07:51:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 1b5d5c17e98ec28319ae36be408e8a20 SHA-1: 73d8b7d2f11c0afc98a607e48f08c5290bad4779 SHA-256: 5a403a15430b212aaf356aded233d9f5a457cd08c4e9de5ec09d8b754d282ff5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan distribution attempt. It contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to 'fundamentals of cost accounting'. No scripts were extracted, but the overall structure and URL patterns are indicative of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://catamma.ru/uplcv?utm_term=fundamentals+of+cost+accounting+3rd+edition+pdf PDF link annotation
    • http://vidol.nl/userfiles/file/83412085117.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16080548b99727---satum.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae78461c95e---nupapewuz.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/ba2cb09090209d24fc82e0520c3c8b25/83682605715.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f825d6bc8a---vixomufidoxirutowi.pdfIn PDF document text
    • https://webfox.net.au/wp-content/plugins/super-forms/uploads/php/files/6125141bca9ced819cc929d3332b4ecc/30647901620.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/8c7de219e0f241bc165796baaf0ce74a/jovewifefe.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/d563dd7ea0772f0b86f83d579b0976b3/majugutofavopemewadinefi.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/ojb2d4486l5i00724fh7kkpse2/5938680233.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade7cc4d03f---gigakodisubikogopat.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/d21b30a9f9e35b1a607c54676fbf931b/diwufegesedukejaduzuta.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607401ba625bf---godepasopupowutado.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608086b6cbcee---29349992380.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/nibamowomufazaxizitolus.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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_off0001008d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1008D 5592 bytes
SHA-256: 8156c6c8f9a8bd08a6fdbc2654fe3f09239bbbb41a22cd5c12cba094ccbebcb2
font_01_sfnt_off0001137f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1137F 11548 bytes
SHA-256: 28fcf819a174cf50a716697fef607902df6d393f8e8c127a1f5b23942dab1f9c