Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc88844a70ae1809…

MALICIOUS

PDF

73.5 KB Created: 2021-05-15 01:58:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 5c9285dae7d67910033a0dd91f79b83e SHA-1: 9ee0c86df02606f75a4a587213a30a6e3f8db8a1 SHA-256: cc88844a70ae18097eaca72b49d9300aa77fb340916cb68bffedf5011fb19e7c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites, indicating it functions as a link farm. The presence of 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics strongly suggests a malicious intent to redirect users to potentially harmful content. ClamAV detection and ML classification further support its malicious nature, likely as a phishing or malware distribution lure.

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 http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081f3e810868---37171900555.pdf In PDF document text
    • http://maihome.hu/admin1/file/70787841522.pdfIn PDF document text
    • http://asbu.net/uploads/FCK_files/file/daviposifosabi.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/78281628033.pdfIn PDF document text
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/ttv67u5ca1d22t786dq8b6bsi1/dalanumifubedew.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5713c9209---janamogimu.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/3373ce5ea2e970c584bbe2106bcf1425/durozolurebifijo.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/e9eigtliqcasbdj8no07o2k234/vedeso.pdfIn PDF document text
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071c12b0c8d9---745544229.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160922af7a1653---95864874278.pdfIn PDF document text
    • https://eobliecky.sk/userfiles/file/3610959874.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/5b09992009fe7383362a97956dc5319e/jowisevagurileku.pdfIn PDF document text
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/o30midenkc58eal9avos0f0ref/gorajutozinixabekajaf.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/7fbacb3ac8b509e20c4be2b26611525d/62482212534.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=baptism+certificate+freePDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD750 4748 bytes
SHA-256: 3b5701c0584392a1af11594b72134c46d511ed4fcc286164d4934678af846bc0
font_01_sfnt_off0000e768.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE768 10580 bytes
SHA-256: b7641d1db074266cf14372b5a37ad6dff8e5022694b21f30335765479c0de7c9
font_02_sfnt_off00010b24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B24 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3