Malicious PDF — malware analysis report

Static analysis result for SHA-256 a72b274af1e24dea…

MALICIOUS

PDF

75.9 KB Created: 2021-06-12 10:43:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 0ddf8905dcca6e5d3c0bd778cbe81878 SHA-1: 5c7335bb9cb5d42fd57caa1eba5793780992a3e7 SHA-256: a72b274af1e24deab1f20c9e9d8154d991ca022a44b065ad20deee8e6d3df738
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. It contains numerous external links, many hosted on compromised WordPress sites, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, appears to be a lure for an 'easy origami frog video', likely a pretext to drive traffic to malicious URLs. No scripts were extracted, but the extensive use of external links and the nature of the heuristics point towards a phishing or malware distribution campaign.

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://synerhu.ru/uplcv?utm_term=easy+origami+frog+video PDF link annotation
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b86beff370b---xopifegu.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803c360b3e5---47539472964.pdfIn PDF document text
    • https://led7.ru/file/medijof.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/b65ebe695c9fb982836c0af50648c280/lovufaxus.pdfIn PDF document text
    • https://bookatowncar.com/userfiles/file/6428227780.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/tuzilomefewe.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609de17e82d06---13911397289.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/23633638461.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/36901289841.pdfIn PDF document text
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/3i0dgg1mevp6upkh75qnpff9u7/91751420740.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/mesoretuvajepivez.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608855c241baa---33013848682.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/g7v51b3i9f67jql67agelkeu1o/45615077632.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/16794328640.pdfIn PDF document text
    • http://aj-logistics.com/stock/userfiles/file/neruzetedelefobi.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/jc3jrn2i7m99ua8gchh1kub372/7189993100.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160716597ae49c---35125341544.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE116 5312 bytes
SHA-256: 1cdd7051e1cc7f9c8366e880a7f82da4d7e37b6811ebf609cefd8e4bfad5aedb
font_01_sfnt_off0000f31e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF31E 1800 bytes
SHA-256: 51ebeec29509b87aa858d500e37ac8853184703d07d1f913ce36d8e1dc7764c0
font_02_sfnt_off0000fbac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBAC 11380 bytes
SHA-256: 2324c90d6f4920df6be0f73b756132e0e64db4a71acff8ad99fcec366c4eaf99