Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa8458a74ba24acf…

MALICIOUS

PDF

83.4 KB Created: 2021-09-04 20:52:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 02324d61e8da486fb04a78bbc63edba5 SHA-1: 76843c82f32ac81563aeb4dc7b248dd900a467d3 SHA-256: aa8458a74ba24acf8e97c81433f9b76fc13a88eea44ac6815ee6c16cf03be395
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage and disposable hosting. Heuristics indicate this is a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature, likely as a spearphishing attachment leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://misosmile.com/upload/editor/files/wigavofi.pdf In PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5af89aea5a---jizomajovuxu.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb405319c83---46889735570.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/40f639030ff166cf587213ef52d257f8/limozaxo.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/1467c5bafc40c64da67fd28f335b2838/70665341488.pdfIn PDF document text
    • http://www.greenbriarpropmgmt.com/wp-content/plugins/super-forms/uploads/php/files/5c4d8beb37b1e9bbfa432899d3387150/vitapumoliruwopunarete.pdfIn PDF document text
    • http://kvrhousing.com/uploads/kujakigominepowov.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606efc98a8beb---bibefesanekagi.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16112fcb04c30f---vokijiwusetololu.pdfIn PDF document text
    • http://navrattan.co/userfiles/file/farazebarerurininadusar.pdfIn PDF document text
    • https://impeka.lt/components/com_mijoshop/opencart/image/data/files/52577960533.pdfIn PDF document text
    • http://samtekelektrik.com/files/96966206714.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021090412163173499.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100555466fa0---86626202054.pdfIn PDF document text
    • http://kartelabasligi.com/images_upload/files/84614714302.pdfIn PDF document text
    • http://smolensk-bakaleya.ru/userfiles/file/nibifawedarisulepusim.pdfIn PDF document text
    • http://autowagon.it/userfiles/files/56828135420.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e8bc3f9f9e9---borawuw.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/3b801107bff2d5b3a3acd2711a57e5d0/lefuronoru.pdfIn PDF document text
    • http://used-machinetools.ro/app/webroot/files/userfiles/files/91622843558.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/jijotegepenuxugodovazifis.pdfIn PDF document text
    • https://www.espaciocultivarte.com/ckfinder/userfiles/files/91881646523.pdfIn PDF document text
    • https://qnzar.com/files/biliwusanabomokupezexo.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/cjj3mg7nmspqipvo4v5cc0ecp0/13840100543.pdfIn PDF document text
    • https://ispartaorganizasyon.com/ckfinder/upload/files/42598051352.pdfIn PDF document text
    • https://veterinarycarefoundation.org/userfiles/file/6630536543.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=current+affairs+pdf+for+rrb+ntpc+exam+2019PDF 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_off0000dd4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4F 18664 bytes
SHA-256: 9bf054f9aff671dbc9dddacf29d755f95c1d47bfbe1cf5030483e649e934245d
font_01_sfnt_off00010c6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012485.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12485 11568 bytes
SHA-256: 2d25c8489a74558713e984f58e4cd5ff7150d7ed21f08623a7bc8b31a679d549