Malicious PDF — malware analysis report

Static analysis result for SHA-256 308d3b250957fcfa…

MALICIOUS

PDF

87.5 KB Created: 2021-06-09 16:14:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 4591882d939138cc8f156b9fa0f8abe2 SHA-1: 9ccabb19fe3a1b2fdc39b8df032bdbb8c32bfeb6 SHA-256: 308d3b250957fcfa7a02e11c3f9b42a22985669339cff27d5795d4d5e2e684d0
164 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 threat. It contains an embedded JavaScript stream and a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The primary purpose seems to be redirecting users to external resources, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=osmosis+gizmo+assessment+questions+answers PDF link annotation
    • https://atl-50.com/files/file/5067877201.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/nezokuzefulujimej.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/6vs6fsj8splakca8i414ih7kmg/32566491608.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/2023eb4d35e87da3cc8d0435dc0ecba9/pufukuwoxiralibarokudanu.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/02qca1vgk2qlluabk56hup9hpg/dazozimezovaxosajawonokit.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/12fc23b1e630843d88c62aa28127f11e/fitide.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/80884164769.pdfIn PDF document text
    • http://studiolegalezullo.eu/userfiles/files/37964020541.pdfIn PDF document text
    • https://www.myosiaffiliate.com/199trust/img/file/80898654678.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/6d25fb724cd5cbc63c57b0e4da8b58cb/digirezululotijo.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/66f085ec65ee308a27ebcc520a4d0083/22753523761.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7484175525---zoxorolis.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160887205016e6---69013588936.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/hds6np1jbj4cscpv9p9mcth8l0/74105466273.pdfIn PDF document text
    • http://ypdtools.com/ckfinder/images_store/files/25441428979.pdfIn PDF document text
    • http://kaizousha.com/js/upload/files/veviga.pdfIn PDF document text
    • https://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2c489ac493312c534b4910c6de6554c2/1556300301.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_off00011899.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11899 5268 bytes
SHA-256: 14d40edeaa19beb7dda7d25995967ceae6dad74db46c9d3401065034ba214a81
font_01_sfnt_off00012a84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A84 11416 bytes
SHA-256: 18b03c6d6bab14a95cdad72f6e0f3a6a7f575b5c242aa4a27a00559fff465b13