Malicious PDF — malware analysis report

Static analysis result for SHA-256 481d9b7bfc36146d…

MALICIOUS

PDF

74.7 KB Created: 2021-09-01 18:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2c548e2bbaedb2b0c786db7884eaa2d7 SHA-1: 2ce54e780a48d6db306e704a974781d887162030 SHA-256: 481d9b7bfc36146d083883ed77f3d2d5d8645dc42d69c0e68ad5e77fff0a545f
96 Risk Score

Malware Insights

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

This PDF file was flagged by an ML classifier as malicious. It contains a link farm pointing to multiple compromised WordPress sites and disposable hosting domains, suggesting an attempt to distribute malicious content or phish users. The presence of numerous PDF files hosted on these domains indicates a pattern of hosting potentially malicious documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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://chieucoingason.vn/files/51750330271.pdf In PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/ass7r9g0pslia0hmd1orlbla4k/vibuwomasinumenudubitoza.pdfIn PDF document text
    • http://chicohigh1987.com/clients/47015/File/92244565993.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/2fed22878105cd6bc546ba95c9f228f5/60433648226.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/5ef99976f4b7c3f40f972f908f324eb3/bivizug.pdfIn PDF document text
    • http://myucmas.com/userfiles/file/6646740324.pdfIn PDF document text
    • http://sobsai.com/ckfinder/userfiles/files/13544450823.pdfIn PDF document text
    • http://csa.china-led.net/static/editor/ckeditor/ckfinder/upfile/files/84379592589.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/55221305611.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e7bf7b7f8da---72520488392.pdfIn PDF document text
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/momodele.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e110827e6---69758802435.pdfIn PDF document text
    • https://greenvalleykerala.com/ckfinder/userfiles/files/palegupekimotezez.pdfIn PDF document text
    • https://drivetripper.com/userfiles2020/files/97314966879.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160760b795f8a3---buwotijibo.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160f5e277dc01b---81020242228.pdfIn PDF document text
    • https://bnbtravels.com/ckfinder/userfiles/files/nogijadotalomatodibom.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608059a9ba191---wamuwikurapifetubofiv.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/6840539337.pdfIn PDF document text
    • https://mygo.com/ckfinder/userfiles/files/wutuvewafaporux.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=die+young+instrumental+mp3+downloadPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bf7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD793 11208 bytes
SHA-256: df0b51906cc514a35987f933e0d41bf3ffdd6b9e96a82e1f7224f081e19cdade
font_02_sfnt_off0000f1b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B0 16596 bytes
SHA-256: 36e4e88d2e462fd71429bd67ea4b2cb59af5167060f139a8d7c90eba44a6feda