Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a1bd38b898c8ca1…

MALICIOUS

PDF

76.5 KB Created: 2021-06-02 22:32:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: fc51c48b2f0af9c230711660f96b1600 SHA-1: 780139efaa87a24a4989de1f2d41f996165f19de SHA-256: 8a1bd38b898c8ca142473942fd7f95d83d7923249925d6dbc487c026ab9941d3
156 Risk Score

Malware Insights

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

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/pkc3kgvjndcl6ff0gkj4v5ds66/64001811873.pdf In PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607174e274f10---81901793095.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ad8ce46350f---dexaxifida.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c9636d019---sopogifolopapafikalenub.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16075896359643---38287703711.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/5d68be5a17b048937baa5b240d00cde9/90550141129.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1607a76626a389---19804042431.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6c375fee1---kowidog.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607852e2de8a9---68875801078.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087c90f76a19---36153414865.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aadb4a05492---64334802449.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f340ae542---dezosu.pdfIn PDF document text
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6e9b54571---30937481511.pdfIn PDF document text
    • http://novussiteyonetimi.com/uploads/file/11167798506.pdfIn PDF document text
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/hu353gu4m2vvkofu5mk03b2jj1/pavogimokitomofugujotoj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=plantronics+headset+cs540+user+guidePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9B 5440 bytes
SHA-256: 3598c1482804608439ebc1ed906c63f0dd993de6d62d924d006e947f348262db
font_01_sfnt_off0000f20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20A 10716 bytes
SHA-256: f871bd7533f6252c25cc4f660579e95dabadb6325be3595edf1d3371fea5f48c
font_02_sfnt_off0001166c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1166C 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361