Malicious PDF — malware analysis report

Static analysis result for SHA-256 da22b31f2af76a77…

MALICIOUS

PDF

97.7 KB Created: 2021-06-24 05:52:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 9d48480f914180346c9271a5f025ad1a SHA-1: f47f0d449aecd0125b53adc34d1f00c8413a5962 SHA-256: da22b31f2af76a77e50361a37686f96909fad478734d3efad61e0afebcaa97bc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=spectrum+general+studies+2020+paper+1 PDF link annotation
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/383567ec8abf4bd8a7a8f26298c3623a/86047903843.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/pra0h7913m5d9e9t9bq7cimukd/21429971929.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2812c2701---pulabuxarupok.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/hbjodprhj4ktd49fv417r68et5/kojuso.pdfIn PDF document text
    • http://etcad.net/np/upfile/file/22130498776.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/49027b4aae3a69057e349dd2c8aecbf0/69951323498.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/xinuveruvowod.pdfIn PDF document text
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/d29f18322d3657e852d3fba52baab8bc/pupebatej.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d00c00bc50---rukavemifeva.pdfIn PDF document text
    • http://abogarestudio.com/userfiles/file/kunekozeke.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/160966f03afcdb---96656963336.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f3ibcbn5jfmmkm06qlrvgn0cl1/puvizejokotulanu.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/c0878c91f912552d2959438574957032/59008283413.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607234af5bed9---wozaketarovo.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
    • 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_off000128dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128DC 5824 bytes
SHA-256: 766cba141455e5b73f9550b6aebe252939b64efeafc6f7950a0bcb760952b6e8
font_01_sfnt_off00013c91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C91 11344 bytes
SHA-256: 3b5ba16f78362974522292093aa089002b923a289c9c3b72d9dce38fc863ecf7
font_02_sfnt_off00016346.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16346 16408 bytes
SHA-256: 936d63d745f9ca546e70ed8e575856951a6c9f17c795c7a47c305d5c484c0af0