Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d559c2df5dfbec0…

MALICIOUS

PDF

69.4 KB Created: 2021-05-05 03:21:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: a5951008a32c2520225afc7d3f664e9e SHA-1: a4cdb806cf3d43dc98a4f0f56110e17e6ee4466b SHA-256: 1d559c2df5dfbec091e0373d08e04d51073f97b4e6767af5ef843b32c7b2d242
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a link farm with numerous URLs pointing to compromised WordPress sites. These links are likely intended to manipulate search engine rankings or lead users to malicious content. The ML classifier strongly indicates malicious intent, and the structure suggests a deliberate effort to obscure the true destination through multiple redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/0vgds0dmvuv7usf472a66mucdr/tirumusiwevut.pdf In PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/ac0c2fc141aa72dbb6be87ded2e9ab8e/puridad.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/4f938e4406c1fde1aa2f7d5480486977/weradixowawidubal.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607da6a30b45e---85772585386.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/16083bee9c7dd0---1876157118.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/r2edkj29m70t3bl5u0v4h0eb60/14319519113.pdfIn PDF document text
    • http://autoshiftbid.com/fckeditor/userfiles/file/22731491309.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090bf8a88d05---53454559028.pdfIn PDF document text
    • https://www.surajinformatics.com/wp-content/plugins/super-forms/uploads/php/files/f64b8d6b5b2c37480e74cc2e35fade3c/takikadi.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160819fa728c9d---86540911365.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16070709e28495---60090728391.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/japonaxut.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/da953f61c70e715c132af5bf60a73e0e/fozadowas.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/iegq914ekr4j51an1bqp5hqi4j/55976573608.pdfIn PDF document text
    • https://cioms.chIn 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/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=cioms+ii+reportPDF 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_off0000d491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD491 4628 bytes
SHA-256: 2dd2e0cf37f81bbb1a4f5bcb20032165ad202f7fd481f588abba199e6b1e460f
font_01_sfnt_off0000e435.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE435 10928 bytes
SHA-256: eb048bd8e6b5088344326d8e78d7f40cec860c0f2870dab71a2577e798c33fbc