Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b534c5812ce6a5a…

MALICIOUS

PDF

79.0 KB Created: 2021-09-21 05:23:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e69c916aba044ae4ed97650b357583fe SHA-1: d6a6673dcefa992a689dd6e09ff649c07d83016a SHA-256: 7b534c5812ce6a5a277f4a091ddcef72201e8597f1600db2cd6069cba3b6a981
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document flagged by ClamAV as Pdf.Phishing.Trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, some of which are compromised WordPress uploads. The ML classifier also strongly indicated maliciousness. While no scripts were directly extracted, the PDF structure and link farm behavior suggest an attempt to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://webrobogo.hu/kepek/99181528244.pdf In PDF document text
    • https://elpollopaulino.com/cenavarra_userfiles/files/80404557918.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/71450148079.pdfIn PDF document text
    • https://weyergans-hcc.lv/userfiles/file/xipujunuzatutegedakogelek.pdfIn PDF document text
    • http://associatedreclaimed.com/userfiles/files/naxuwawizar.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/0aki6m4ns5nkb74u0aomkiedp7/4777746676.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16137b476c83c6---19841947206.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/duwowusamogamekiju.pdfIn PDF document text
    • https://jjcfurnituremaker.com/userfiles/files/9976092458.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/subof.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/33699394306.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/97531036539.pdfIn PDF document text
    • http://vtaky.sk/media/file/menilojile.pdfIn PDF document text
    • https://sunsetlearningcenter.com/userfiles/file/78157704136.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/8a464bfe783d2622352ea8af3a4b9f9b/34065469779.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16138b8a9b6d4d---wawenejipalomezonalas.pdfIn PDF document text
    • https://msiutilities.net/documents/rovodobepukiwadoxajudubi.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/kuwizokubologij.pdfIn PDF document text
    • https://impulsa.mantareys.net/uploads/plantillas/files/64962959207.pdfIn PDF document text
    • https://lawyerupsmart.com/tempimg/file/9235195229.pdfIn PDF document text
    • https://soi.icami.mx/ckfinder/userfiles/files/vujubov.pdfIn PDF document text
    • http://artwatch.ru/userfiles/file/81009931141.pdfIn PDF document text
    • http://wu-pao.com/upfiles/editor/files/sufetujulokenoxogenojap.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/6368257544.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=superstar+smtown+downloadPDF 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://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_off0000c8c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C5 19660 bytes
SHA-256: 7ff1d33a0f01d225e937197c5359a8132b0f8f63ac8f67c71d0d7d5428f84235
font_01_sfnt_off0000fd72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD72 10724 bytes
SHA-256: f7b69fe93f3eee5bcfb51bd2d371d7e8211d07921af08f9128f76051560ecf7a
font_02_sfnt_off0001161e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1161E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1