Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ab984f3265776e2…

MALICIOUS

PDF

77.2 KB Created: 2021-07-07 12:01:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 39f9e89dfd0d191be4d3e17ce5abed98 SHA-1: 3978a0cfc6bced75f41b462e32d56a306963479e SHA-256: 6ab984f3265776e27780f327233c963d87beaed23c8a8d08c7fe0d77a3ee4c93
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories, suggesting it functions as a link farm to distribute malicious content or phish users. The PDF structure itself is heavily obfuscated, and the document body is unreadable, further supporting a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16099c82438042---25651286918.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a768c68c2---65938750187.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d1907f7bc73---74120710755.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609adf83261dd---39222476499.pdf
    • http://eros-arena-reutlingen.de/eros/userfiles/file/rixosefamed.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d62731541f3---luvadurijibowazokofomunel.pdf
    • http://self119.net/upload/userfiles/2021/05/files/210529144232.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/6k5rbch28d3uosigs8c1ri481h/vifozewirodijor.pdf
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/24i1n24nenkr3hu9tc0hjf6hm1/30380415090.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/vegatajumuxilumuxovimifi.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc9477e30a6---webozire.pdf
    • https://agronlogistics.com/userfiles/files/81021370211.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/dc339cf4a7e3a738a82c8e82c7b9ef02/luvaxilom.pdf
    • https://deesudcoolingtower.com/userfiles/file/48123544816.pdf
    • https://binarbaidrealestate.com/public_html/userfiles/file/pesupekifakonibararifane.pdf
    • https://alarrabnews.com/images/content/content/file/40741993612.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/727982df5378fe3dcebad20c58bd9031/84078483713.pdf
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/94156dd9d76f66bff79f0482b6ef0ce8/vewodowetikan.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5da50d088---lepezuvopi.pdf
    • http://suvagcentr.ru/userfiles/files/dozireg.pdf
    • http://tokstar.com/_UploadFile/Images/file/zogidubasefajepuj.pdf
    • http://www.contectrade.hu/fckfiles/file/35057147266.pdf
    • http://rltclassof1970.com/clients/8/8f/8ff9f19c840b982a6efda18ba8bb483c/File/80868738094.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b21d374ade8---jemulutere.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=you+served+well
    • 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_off0000cbe2.bin
e6e78a04593cadaa65d658cd063ff7b1cfad3b71d5f0bc5101354fb939381174
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE2 17272 bytes
font_01_sfnt_off0000f903.bin
3eb16356a1379c4917a09a0c1ee1f71cee219689303c511c9c96134c92af7d05
pdf-font-stream PDF embedded font (sfnt) at offset 0xF903 10020 bytes
font_02_sfnt_off00010f74.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F74 16792 bytes