Malicious PDF — malware analysis report

Static analysis result for SHA-256 43e0c3781ae69bc0…

MALICIOUS

PDF

72.8 KB Created: 2021-06-03 11:28:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 4ec3f890150db245cc32e28914469cc5 SHA-1: f501cae0910f9426cac250bd59c8999a2fae1122 SHA-256: 43e0c3781ae69bc0a00346b088a540dc3173afb8a465c69a4d4d4a1fdeaf5ef3
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites. These links likely serve as lures for phishing or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://refour.dk/wp-content/plugins/super-forms/uploads/php/files/799fac61cf039116c991d54b3f32cb18/safirosogarozulobogesib.pdf In PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608558b93338b---wapegijezemepu.pdfIn PDF document text
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/525lfeplfaipha7cj58cs1pl85/64754773464.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/4840ad2c5a3ec17071627976e2c591fc/6229784828.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/5a6926147687d7b880d415a6b5eb708e/62808901131.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bc9e776f4a0ad3a9b0907f16f75aa5f2/dalaxipozibixakipaju.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607e3a2cbeb86---95375808321.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/s6krtp9tc0dk7vv4tukhtfrjcf/35417430659.pdfIn PDF document text
    • http://happypalettebnb.com/CKEdit/upload/files/70415397757.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/5c64e4cc798a86c60cc67fde4f7c268f/56849460637.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2ea5d61f6f---44627308200.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/jexufatufazokekenux.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/68893029787.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/3235507873.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/7g836fq9q8b33oaah82q6480qp/51858405226.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/fzgW7-mxBc0/uplcv?utm_term=historia+de+los+elementos+quimicos+de+la+tabla+periodica+pdfPDF 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_off0000dcf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF6 5528 bytes
SHA-256: 8e46ab9a4e85f98ea06f7dcfbe2cc1e8cc0fdea64f8e462e5c21c4c346dc2497
font_01_sfnt_off0000efa0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA0 11148 bytes
SHA-256: 24f7f98d5380f4bd8aacb7e96101b6a4bcf84b27da4e364332f9020be7ddf6ae