Malicious PDF — malware analysis report

Static analysis result for SHA-256 1bca865b5d1e873a…

MALICIOUS

PDF

74.1 KB Created: 2021-06-15 18:22:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 89df6401d70b4c5ed13ddf7d7ad8602b SHA-1: 776a52ed2f7ff27e70185284c5797cffb4ce8500 SHA-256: 1bca865b5d1e873a3aec072fedd69efb3ea09fd0748e1e8d69de777ead5001f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to compromised websites, many of which are hosted on disposable domains and utilize form-upload plugins, indicating a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or delivering a secondary payload via the embedded URLs.

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://infrive.ru/uplcv?utm_term=find+probability+distribution+function PDF link annotation
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/4ece8e2bbae852ea6357c577d3e89844/xowulixusap.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608aecba3a77f---88015975601.pdfIn PDF document text
    • https://contactfm.be/userfiles/files/90764970979.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/a4364d55a3d4f0a00d45f06a4f98e2df/suxanuzuwaxukegaxuwazude.pdfIn PDF document text
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/03cdbaf4043829798e02bea10ee8f727/16040547356.pdfIn PDF document text
    • http://goodslib.com/userfiles/files/mebikadafoladifadajok.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/o6n64g3bk80n26q3emeg4mscv2/somabixivisidole.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/8ad79c17e13d6c9587446b90c91e92e3/wuvusowinid.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/d82e41123e43508fca57aebb5a266079/venalepuvopajavanoxu.pdfIn PDF document text
    • https://almoheetmanpower.com/public_html/userfiles/file/45332908239.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/96669123106.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb31d1d7d8---mesoz.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/32l5e9k27706gc88n42smt8f6k/25938889468.pdfIn PDF document text
    • http://holycrossyouthministryasp.org/clients/f/fa/fa15eac34f6f8ef5a8ada011ffef1578/File/vinasumifewowojubuzemesew.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/75566869e8d00c45f670c85a4097a35f/77321783959.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af9c617a50a---masoliladirumisebi.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e787.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE787 5348 bytes
SHA-256: 6bb8c86256194eb5ada3574aa10af8e546356f4839a840258552db0413967f5c
font_01_sfnt_off0000f9c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C8 9840 bytes
SHA-256: 390e33b8ea93d9ca03c14cf42ec3fb9f0413d4cb5dcf1d272493fa77ce041e11