Malicious PDF — malware analysis report

Static analysis result for SHA-256 88f9ddc533b7b664…

MALICIOUS

PDF

76.6 KB Created: 2021-06-26 03:23:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 6e4f9098c5a31a05dbb2f321f4379c0b SHA-1: 5dddd8cc683aa833a17fe2dcbe7f849930b3c729 SHA-256: 88f9ddc533b7b664e5ba86777d548e659c78fcc73658226116195c4def249199
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. This structure is indicative of a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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 https://micast.de/wp-content/plugins/super-forms/uploads/php/files/hs6d5sgfpnr7gu5vikhsq9f4qa/78953882143.pdf In PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/ab9fc14ec3acabc6a1cf54ab047586eb/kasumeragupaxaxu.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/981c744666f31a3778f4a1274f2f29c3/fuvinowaputebujupafububam.pdfIn PDF document text
    • http://nutricion-intravenosa.com/wp-content/plugins/super-forms/uploads/php/files/e30e915d23adc9401b4bf544c0247adf/gexolodupizimuvopodafiw.pdfIn PDF document text
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084066864ea1---bagemelidedakabakajedi.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16077496d8113c---fuletikak.pdfIn PDF document text
    • https://kermanrooz.com/img/files/gelilas.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a36f77dbf5---satotavelog.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/c84e839857447844820b96009231db3c/bemevojemam.pdfIn PDF document text
    • https://cochleartudaskozpont.hufiles/fuvibubifo.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/16085791a14b07---werinalidedizeziliwosobo.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086588a23fc9---fefovesadaroxes.pdfIn PDF document text
    • http://accronline.com/userfiles/file/xotubegu.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/fpscmth47tolja8cl3ev65t206/13103142529.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a90a9eea3---90161740031.pdfIn PDF document text
    • http://congtrinhnhaviet.vn/upload/files/11249136611.pdfIn PDF document text
    • https://murten-hotels.ch/userfiles/files/nuxidarabimewakewime.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/1758819877.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/ramodumajedixudasikokedo.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16fbce4870---46904122169.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/dafisetug.pdfIn PDF document text
    • https://fotovipvercelli.it/file/43096851910.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16083b11e1ee5a---guwilojiroponodowimam.pdfIn PDF document text
    • https://5uempat.com/contents//files/56237894751.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/0e434db631177ec5f10d898553c087bc/demon.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/fabc1375fe001f556d045bc5cae5b5c3/4416193445.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16077b21130962---2632286591.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/0k5f8pfp0tnq25s1ufcv7bc3op/2746634108.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=biology+12th+guidePDF 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_off0000c8f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F5 16912 bytes
SHA-256: 59c32933ba2c30f8cc93d4e032b6cb8c76986ed3e8a69e4a6331a8e3ea98a248
font_01_sfnt_off0000f55c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55C 10432 bytes
SHA-256: b7da8556da2333c7d0f35aa25dc39007af7a156e8b364f7dfbba33d0a346b87b
font_02_sfnt_off00010d12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D12 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1