Malicious PDF — malware analysis report

Static analysis result for SHA-256 547cd1b6bb255a0a…

MALICIOUS

PDF

102.1 KB Created: 2021-06-14 05:20:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c898484b70882ca17678e16ee5d32f36 SHA-1: e9f6ef812f1e76f34f615ec7e37a22fed34e2465 SHA-256: 547cd1b6bb255a0a40423cff1cc2221f8f8095b1386d274d63d6db4eae9a0275
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The document body contains garbled text and metadata, but the presence of multiple external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly support the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://chcial.ru/uplcv?utm_term=el+principe+de+la+niebla+carlos+ruiz+zafon+resumen
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/ad0e990fdaaabf361115ea69e4d42821/92233676099.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf6c4a1b461---81100972444.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160739ee56c7e4---xutasuranedufise.pdf
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/ukhod169pu4vkauhp9tgdpunma/29538788330.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4773b5393a---niwakubatoxes.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160849cdf4abed---68402331960.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce7440934a---33895653475.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16096c793a1f0f---wamaxoxu.pdf
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcb95a2e0a---59547636711.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/47008c473cfc9b46ead326b8b64f5e87/wepesofi.pdf
    • http://vitanova-cattery.com/upload/file/48216032882.pdf
    • http://bainihu.com/upfiles/editor/files/99845661511.pdf
    • http://pensionpoint.cz/userfiles/files/pugubibegi.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/d313d70ee33efea983b961ee4c29cf2f/83330303222.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/03810a3250b04a9bc4bf2c2273a408b0/degawigawitamudabu.pdf
    • https://www.propertyadvisersaustralia.com/wp-content/plugins/super-forms/uploads/php/files/c81b7e48090e34867813951191153fa3/86954841470.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000141b2.bin
0e1f9ad092a9a094796757b318018636fdbd4b7d5daa59574d1fae02e4852e3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x141B2 5248 bytes
font_01_sfnt_off00015363.bin
5ebafd36eb22c434e4db6059bdc4ac6e9d653e76cb4179a406eb7c36ecb2efee
pdf-font-stream PDF embedded font (sfnt) at offset 0x15363 12448 bytes
font_02_sfnt_off00017b35.bin
ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x17B35 4324 bytes