Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec90ad373d542ef6…

MALICIOUS

PDF

87.5 KB Created: 2021-09-03 01:10:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2e4fb53e71da6f6a3b544ca2f68e53ae SHA-1: 7131cd7c6b90687688b62122b84f57121bd9dbb3 SHA-256: ec90ad373d542ef6d4875de2a42e2b259d7b131458ac0ad83d99e1990f20e17d
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicates maliciousness, and the presence of embedded URLs points towards a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/klcr5bt4jsou9k6bfd12onv2t7/72447741397.pdf In PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/45883523088.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/sunomekapupud.pdfIn PDF document text
    • http://taitung-house.com/CKEdit/upload/files/13419419003.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609704ce6a83a---taxop.pdfIn PDF document text
    • http://beauty214.com/uploads/files/202108220816447556.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/51893087934.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/3ut1i2gl3jhubnv1p2rg83tqrg/misafopuzoxuwezamiveni.pdfIn PDF document text
    • http://henri-ruch.ch/doc_pub/file/17247168972.pdfIn PDF document text
    • http://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/regateja.pdfIn PDF document text
    • http://atomleasing.ru/media/File/jamarukatoxotijoj.pdfIn PDF document text
    • https://people11people.gr/uploads/File/golezipasisituzowipetugif.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/86297497645.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/04304c5ab993cb620204fba95422c96c/vuzijukixuvori.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097c88ceb598---72240066622.pdfIn PDF document text
    • http://cjcounsel.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kajola.pdfIn PDF document text
    • http://viermaalh.nl/Bottesteyn/Site/afbeeldingen/file/95886061911.pdfIn PDF document text
    • http://trivio.it/userfiles/files/digunatavuk.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/daxezeraduj.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/86786867823.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/zogunapofal.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/7612e018bc2f3feee9a72bed17668f56/76408060801.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fe678744d9e---18460987114.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/bogezosemupip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=pdf+editor+tool+onlinePDF 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_off0000f11c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF11C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010933.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10933 10020 bytes
SHA-256: a4d472ed095e13a8deeb33c51f5174d9add0d21ec0a309440d3b02dd6c8b7bc8
font_02_sfnt_off00011f7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F7D 19008 bytes
SHA-256: 3706a7da3b677fbe84719f30e315bd493511090c69d35d8ca5e0dcdf7b4aa0cd