Malicious PDF — malware analysis report

Static analysis result for SHA-256 c804766ac06ab890…

MALICIOUS

PDF

81.9 KB Created: 2021-10-07 04:48:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9acf671c3e45c4cde03732b789cb3b79 SHA-1: 240b875b1602c0c48a4c37ec40b5a57889834247 SHA-256: c804766ac06ab890422a4c21d9efaefa1829a813ea9375dc9e798fe3e80d5972
96 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous external URLs, many pointing to compromised CMS uploads or disposable hosting. The ML classifier strongly indicates maliciousness, and the structure suggests an attempt to lure users to potentially harmful websites. No scripts were extracted, but the overall pattern is consistent with phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://crewmak.ru/uplcv?utm_term=facetime+apps+for+android+phones PDF link annotation
    • http://p-itos.net/admin/userfile/image/file/65491722720.pdfIn PDF document text
    • http://avtokapriz42.ru/userfiles/file/zujivi.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebf457c166---50301333492.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613643b780406---15616361133.pdfIn PDF document text
    • http://ppogrimall.com/upload/editor_image/file/zejulunarokaxogadirexiwav.pdfIn PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/85737219965.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/47651859777.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/90637685706.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/39364078042.pdfIn PDF document text
    • http://ideal-site.ru/userfiles/file/woleg.pdfIn PDF document text
    • http://konberdbio.com/upload/files/10003592690.pdfIn PDF document text
    • https://maytinhdalat.vn/images/uploads/files/1977424127.pdfIn PDF document text
    • https://vietnam-pump.com/userfiles/file/vigalo.pdfIn PDF document text
    • http://dragonera.cn/admin/userfiles/file/tegoj.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/94201668333.pdfIn PDF document text
    • https://www.channeloflove.com/ckfinder/userfiles/files/vupevugidoxizo.pdfIn PDF document text
    • http://shendaoguoji.com/data/attachment/file/95827585676.pdfIn PDF document text
    • http://5thaveseniors.org/userfiles/file/kejolebugudibuxunewamewax.pdfIn PDF document text
    • https://yourwebcenter.com/files/file/badejapuleduni.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/62177119235.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/nujagugekoxagupajis.pdfIn PDF document text
    • https://coluer.ir/documents/file/pawumoferelizunapitukoj.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615910bff1a2c---22011628979.pdfIn PDF document text
    • 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_off0000d839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD839 10816 bytes
SHA-256: 91e572ca3b33939ccaf6c8bf0d1369c4b4fc1a9bc8afd8b23de50621bbfb15c9
font_01_sfnt_off0000f0f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010906.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10906 18916 bytes
SHA-256: bd131a5924bf6309faa3d8681252d947593316a82cb414d64201da15241a8cdb