Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a74a00f92aa7c60…

MALICIOUS

PDF

70.0 KB Created: 2021-06-22 15:45:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: b86f535b45047d7d7b4a536574b28fe8 SHA-1: d7a4f24106c1a362cc1f5f3651fefddab35d4e11 SHA-256: 3a74a00f92aa7c60fdd6383f6f502cbd4153d2f87dfe7fd3c0d71bcb7ab7b429
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external files, many hosted on compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host and distribute second-stage payloads.

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://h-st.nl/bestanden/files/dutaralakulisusa.pdf In PDF document text
    • http://mwflower.com/upimagesfile/%5C/61039805672.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-22/20210522174257831075.pdfIn PDF document text
    • https://amblamy.ee/upload/file/60401238659.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/81321508240.pdfIn PDF document text
    • http://skyfestival.kr/ckfinder/userfiles/files/69645751208.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d67d34f6a2---7121803307.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca29771e3f---38532115060.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/530b88bc7a726c8b9b6e52fc80ab09a7/50645286240.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/77596111728.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e5551145e1---nikedubu.pdfIn PDF document text
    • http://www.tramag.pl/upload/file/20021089503.pdfIn PDF document text
    • http://sahamit.net/userfiles/file/47806575981.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/893b4bb71215467a2d61b53aa59175ea/datuwimetanemomejisobir.pdfIn PDF document text
    • http://royalgoodviewresort.com/Uploads/file/jamudavewiwab.pdfIn PDF document text
    • https://artenika.pl/fck/file/52040867092.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/61826684508.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/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=download+kumudam+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC861 4704 bytes
SHA-256: d98fdecb95054380116a4feece5670e79a8adefe9cee6e32dea99b0df5b7cc39
font_01_sfnt_off0000d858.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD858 10896 bytes
SHA-256: 96f33bd8eaa2757951a10c5081eace919075d8aef1a35e7d80d2dd5dd880d870
font_02_sfnt_off0000fd22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD22 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3