Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c81f4c1ed4e9b3e…

MALICIOUS

PDF

92.7 KB Created: 2021-05-27 15:48:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 0c77fa525a3f6c30839ddb97a120f27f SHA-1: 2d0c0b2c1f0a64e6771cec51ed5d84d36eecc04a SHA-256: 6c81f4c1ed4e9b3ecb77ddc569371ba2e74a15b34af9bbe9fc7cc489e7c4639b
156 Risk Score

Malware Insights

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

This PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file functions as a link farm, hosting numerous PDFs on compromised WordPress sites, which is a common tactic for phishing or distributing further malware. The presence of external URIs and the overall structure strongly suggest it's part of a larger malicious infrastructure.

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 https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/315944704f8dabb52c2f06b2b9821c82/71410760159.pdf In PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9b45e2c75---51363248833.pdfIn PDF document text
    • https://forcechicago.com/wp-content/plugins/super-forms/uploads/php/files/8c94112c4242e7177f4f0ba1398cb234/tabugaxuwemudizimik.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/cbac03664f052ad22af1ec47c5f45c53/tavokonolusali.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608c7c355d296---69705535519.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/fe55fdda0af0c964dd3118afcdcc39bd/vatolubalovalag.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607495614519c---54290883652.pdfIn PDF document text
    • http://soflocops.com/clients/67403/File/gabotugatigumawile.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/b171b3caf5773596d97137aed99ca99f/lulajimokikesodipoxuto.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/16086024324c53---larozowinavezifewasujuz.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077da30253d3---77225039560.pdfIn PDF document text
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/84cf2a136d726e1dd92117ce8e4cf3ba/68923778020.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/b0dc13bf29ff5a380cca7a6222b8bce5/5230091946.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e49a3053b2---36259747010.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6c2e97365e---46812710045.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=how+do+you+describe+your+character%2527s+physical+appearancePDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012d6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D6B 5492 bytes
SHA-256: 310d5ce896d8d0d57d884ae962020daf54d691ae87be1bff1d7f29805f865949
font_01_sfnt_off0001402b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1402B 10976 bytes
SHA-256: 017a81c7b4dc40365010019695059a5db8d9650460d3e4db70695c657d951a9c