Malicious PDF — malware analysis report

Static analysis result for SHA-256 f20ddb0b8a7f5691…

MALICIOUS

PDF

88.2 KB Created: 2021-06-29 04:44:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1b5955adf93ba4f8b3300262f7d7c5b2 SHA-1: 15ebc03b64d6867b0db904634cf7b2ead44298ce SHA-256: f20ddb0b8a7f5691032de2ea1cd3400ffee0036ee16844f34992e6bf3d8da816
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, likely to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/5sjeh5fkcnksd5a93kh8p6rgpu/rasapekir.pdf
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/0q6nt10dl9730r8cnttkuvvd85/14576556988.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/231dfeda14200ae1f448d0de6d3bd20b/6291890705.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607d34998dd6a---88310814017.pdf
    • https://vibangnhadat.com/uploads/files/69262244358.pdf
    • https://broadcasthub.com/ci/userfiles/files/kerejegusajagumuwunedizan.pdf
    • https://tepihtrava.rs//files/menuvewezabilolalenewexo.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/9a43f3b1da3622f3fe1ce8d4581e6464/tedatelezanabuwaz.pdf
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb7950235b---wilelepatiraxunozel.pdf
    • https://dcmheavyequipment.com/admin/images/file/44742598680.pdf
    • https://ltssinternational.com/res/wysiwyg/file/67625925112.pdf
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aaac33915a---30127548306.pdf
    • http://files.ibiza-ferien.de/file/ziwabonevebobajove.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/dc5a48b31b1b384e43304ca9b15b4b00/zusugemuma.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085cfb2c8bef---gixozugivojobe.pdf
    • http://chromowane.com/userfiles/file/zaxuwudalapifi.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/7a0b9e097527e345648915071e8e2597/67815841841.pdf
    • http://olimpic.hu/ckfinder/userfiles/files/jozufibo.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a843cce9972---72688118650.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/335c30c8824fc742e054f89e44c465a4/2901502206.pdf
    • http://studiotecnicobonoli.com/userfiles/files/gixuvomib.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160cea613b220e---59916428804.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c214c482a54---26479858331.pdf
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b2a91e0f7---gokuxebopeponasux.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+do+a+manual+in+skater+xl
    • 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_off0000f2f7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F7 16792 bytes
font_01_sfnt_off00010b0e.bin
ac2e26de74b1cb2f6385739b1a5f4ed4961671b224565e60256ff4f9c42db32a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0E 10780 bytes
font_02_sfnt_off000123db.bin
834283bfe4183b6f15e3ed9399cb8bd7f37b93d51a5e3436f5536baab22a076d
pdf-font-stream PDF embedded font (sfnt) at offset 0x123DB 17456 bytes