Malicious PDF — malware analysis report

Static analysis result for SHA-256 13ac8333e2d25aa5…

MALICIOUS

PDF

82.9 KB Created: 2021-09-02 09:05:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7618bca0b33d8bc0b086436c0ca8001d SHA-1: 9086c331dd775f10509c8c41ab5ddd03e756a97d SHA-256: 13ac8333e2d25aa50bb565fed04c99a826f7b5ba07a44bd385f968375246bb1f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS upload storage, suggesting it's used to distribute further malicious content or phish users. The presence of multiple unknown URLs on potentially compromised sites reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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 http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160796053dce12---98148997773.pdf
    • https://vinacomvietnam.vn/uploads/news_file/24383030127.pdf
    • http://animalscipublisher.com/files/upfiles/file/gobunitivewote.pdf
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16082623635023---54168544850.pdf
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/rp1516mdh8vu99eg7nacbb5lc6/wekarow.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/1ovlge2tu6ukg8qi4f88u27fkd/kiwajowori.pdf
    • https://pharmawell.eu/ckfinder/userfiles/files/41568445465.pdf
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/6b9e51a8345d7d2809b6c56762fba70e/66717561824.pdf
    • https://aljuboori.com/userfiles/files/37560223779.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/26f4b1e0d693c19478c76bcc05f06be7/wopulufiw.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160892ca88a485---57942574724.pdf
    • http://asesorgubernamental.com/images/file/pibibokujusixakef.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9956cdc9a---89817533037.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8b6db6f09---58656059389.pdf
    • http://savitapiti.org/ckfinder/userfiles/files/molisenorusasipanarufam.pdf
    • http://soyaksiesta3.com/userfiles/file/51538924887.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/ffe7e2d67492fa3afa0d9b1199a6defe/52782510140.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a20cedc8cf5---51553804790.pdf
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/femekubepamosixatoviwe.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/q17hgshhtci3r6oo3tuv4dmv1e/41440435053.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea2793054f---9516055779.pdf
    • http://deauville.ru/files/file/98230317102.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/1d0fb563cbfc8c441bbed668df509fb7/35210314438.pdf
    • https://iringmalaysia.com/ckfinder/userfiles/files/81834777312.pdf
    • http://superazs.ru/images/news/file/87838742767.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=garlic+toast+in+oven
    • 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_off0000e070.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE070 16792 bytes
font_01_sfnt_off0000f882.bin
1821ff85b73cc13444c364ba6dc11e912bac9844b6e8b22f5395d39f94871d96
pdf-font-stream PDF embedded font (sfnt) at offset 0xF882 17632 bytes
font_02_sfnt_off000125bd.bin
afc10636e71281aed333821f26367d68333530ad0b307c12af586b1f1226732b
pdf-font-stream PDF embedded font (sfnt) at offset 0x125BD 10328 bytes