Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b50e3c04221c7c4…

MALICIOUS

PDF

74.5 KB Created: 2021-07-03 15:54:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c3e41d8ad6d36778c4903b27e6c0cf00 SHA-1: 31ef87846c7627cccb901bb280c3c89c3e7a7c78 SHA-256: 4b50e3c04221c7c4219619de75b1b3cf8180023987f1e0823febe3a9ff6babc4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm strategy, and the 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' firings strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, but the presence of external URIs and the link farm structure point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://laborke.ru/uplcv?utm_term=lewis+structure+so42
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/fimopifuwawipumuxelose.pdf
    • http://dermalab.pl/userfiles/file/48120916010.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/a3c0510f60c54a3a8aecc8b5496b4b23/lerasofupamenidoguxaluko.pdf
    • https://secolink.sk/userfiles/file/59679158095.pdf
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607991d257f16---99297406228.pdf
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/07014dbc71a65e3bb8a92677761ab811/67740417929.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/b604823d49d4d1d19cdc279a35425f9c/40783088541.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/dc9c6e9910550119fe01944b693d003c/40268334660.pdf
    • http://www.houstonorientalrug.com/ckfinder/userfiles/files/33009773263.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/is0gro90blsjbrir9kjo7teb41/jatemovifexakisazox.pdf
    • http://ixtvs.de/_upload_bilder/_filemanager/file/79439944542.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b1bbe9ff38---39555679631.pdf
    • https://eslms.com/userfiles/file/timurekurilabituraxen.pdf
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/77086741560a8e188ee2b0.pdf
    • http://studiospazioambiente.it/userfiles/files/nufisumefasusaxerizubisal.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/c750f3ad8fab59bcc2396b295df2e88c/49319444628.pdf
    • http://changrung.com/ckfinder/userfiles/files/povetukokewejizoli.pdf
    • http://samrayburnclassof1980reunion.com/clients/873185/File/gemakawifugafadowimos.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086dd4125223---56994317832.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/aa43534deffaa68e2ea63d9619b7c893/wobakovazesulewati.pdf
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160c74a8f02776---3174826381.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091bfc750ced---dowajegalovazovoke.pdf
    • http://alexlunacoach.com/img/editor/file/61114264746.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/7a57cc705491535c339bdfdc68e48156/78856415349.pdf
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c18b.bin
1e283be799e35985349533d1efe57da517427d0be26eb9f3158f5075a6642e42
pdf-font-stream PDF embedded font (sfnt) at offset 0xC18B 16852 bytes
font_01_sfnt_off0000edac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAC 16792 bytes
font_02_sfnt_off000105c3.bin
5fe7862a42d49a9473e29b5d3a02d43dc84e6b5b15adfb2d9f5f7ce629f4498f
pdf-font-stream PDF embedded font (sfnt) at offset 0x105C3 10252 bytes