Malicious PDF — malware analysis report

Static analysis result for SHA-256 73301e640555429d…

MALICIOUS

PDF

67.4 KB Created: 2021-06-25 08:11:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: b7c26ceab3c684f4050f9d2c334f01b8 SHA-1: 81f537d55f9ee50d5faf7c41f4be89f2ff620465 SHA-256: 73301e640555429d005674393c1e03672aabf5f7c3dff7de3c60a5fc913c6dc5
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting it functions as a link farm to distribute malicious content. No scripts were extracted, and the document body was unreadable, but the heuristic firings strongly indicate a phishing or redirection attack.

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 http://www.asslar.de/downloads/79452098406.pdf In PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160bb5690d766f---wivalalozufukovew.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c52e929d676---senejega.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d60ae3103---89265128497.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7516aeb59b---wugelawavi.pdfIn PDF document text
    • http://bjaimama.com/data/upload/2021/05/file/202105132219334294.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a00f1d50cdd---pobegafibogusi.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/16095bfe7dc443---fuwipudodewewor.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/1c0tu3kvtr4fp1uujkg0bcc5k1/25133408162.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/damiletasokoxevidovor.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a86d60ac607---dagabumivora.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/jenagizuzudovarab.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/b04ad1157df221adfb34a10358d186d7/67527870694.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c704c827f94---48821935695.pdfIn PDF document text
    • https://thehero88vip.com/ckfinder/images_store/files/jakisutinolanepejod.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/75892226479.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/~3/6naE_Nh8_CY/uplcv?utm_term=physics+3rd+secondary+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_off0000cab4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAB4 5480 bytes
SHA-256: 759f3bce6a535feff8a1bdd69a7ad02d53b826c80292dc8b6729fb0554e07ca3
font_01_sfnt_off0000dd57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD57 10464 bytes
SHA-256: e57a13891cb432745bc3f6b6d4850320a558e163efc19012b5f4d45c05d2dce9