Malicious PDF — malware analysis report

Static analysis result for SHA-256 1be67d0535e4e841…

MALICIOUS

PDF

71.0 KB Created: 2021-09-01 09:09:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 79cfc06525015c3a32ffc6a2ecabcc54 SHA-1: aef76da43b937bfdaa77a189a4678b545bf0d362 SHA-256: 1be67d0535e4e8418ba46f6ac4bfb3122788393237fc9b72830a06bb2e8ce8a5
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier, indicating malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to compromised WordPress uploads and disposable hosting. The embedded URLs and link farm structure suggest the primary goal is to redirect users to malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://coretry.ru/uplcv?utm_term=shuffle+words+in+a+sentence PDF link annotation
    • http://ajisushionline.com/uploads/files/gowisetidega.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607d22fa22c58---sunabelivo.pdfIn PDF document text
    • http://f1-rennsimulatoren.de/userfiles/file/belilijig.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/54455709763.pdfIn PDF document text
    • https://ekransamara.ru/files/22396866605.pdfIn PDF document text
    • http://sayarbobinaj.com/file/74469304817.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/kiparusavavejotitajisut.pdfIn PDF document text
    • http://drivescuolaguida.it/userfiles/files/56576290632.pdfIn PDF document text
    • http://rapet.hu/files/35689475329.pdfIn PDF document text
    • https://vaynhanh365.net/contents/files/17700149079.pdfIn PDF document text
    • https://qfse.co/images/uploaded_files/ckfinder/files/1627557372_52ede88c85.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e335bea685---keguwob.pdfIn PDF document text
    • http://haniltm.kr/upfiles/editor/files/vixujixufu.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/92466978450.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607150d247768---17545025956.pdfIn PDF document text
    • http://cjandjunemillerfarm.com/clients/75830/File/muwumiwiter.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/f523f2830058c6eb736afed85d1dd2bd/19600567180.pdfIn PDF document text
    • https://jahanchart.ir/data/files/file/87581373004.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea00d7653d---dozuga.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/lizakulozemijunuteruxaz.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/83207672672.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/8e1c9404a87cf8526321e99d69186ad2/8242260466.pdfIn 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://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_off0000b4b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4B8 16128 bytes
SHA-256: 07a943e79de57ced03e935414829d84416e06b7303a4b7da4ca8a1ef9687317c
font_01_sfnt_off0000ddd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5EE 10836 bytes
SHA-256: adb7d5549bcfe01af2a8adc55c063dc78f33547eb9fb6a51eca9fd74a1514aed