Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c86f077a5d9e095…

MALICIOUS

PDF

87.6 KB Created: 2021-09-22 10:34:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 34b55c699893bfd2843e972b5597846e SHA-1: 3a6282cdf3ae69f47681d6382b5d9e123d67da1a SHA-256: 4c86f077a5d9e095fbe14f103b94e8f300fede8477da137be0b33552fb183044
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and disposable hosting, likely intended to redirect users to phishing or malware distribution sites. The presence of external URIs and link farm characteristics strongly suggests an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://amblesidewindermere.ca/fckuploads/images/file/gizifujodavalisu.pdf In PDF document text
    • http://deborahmayerlawoffices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/78771642444.pdfIn PDF document text
    • http://modaxch.com/userfiles/files/wolopudulavopinosi.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a49c1a67ac---vanalowidironijo.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/3092e4f605e0c62179a4db91cd86d667/4583415302.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/cs4m0p9024cfon8cs8ll6d0ai1/52447833943.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/dff4f65725c0928c9ca4e0dda0a66606/guvubagaxevatebuzomoz.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/vodebomak.pdfIn PDF document text
    • http://guowangcable.com/d/files/duxosugosisuxu.pdfIn PDF document text
    • http://aotem.com/data/home/qxu1780220113/htdocs/uploadfile/files/27734096810.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/posafejavo.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614adbccc075d---58544282899.pdfIn PDF document text
    • http://sxnqx.org/upload/file/Fl202109152236562440.pdfIn PDF document text
    • http://centreforeffectivecoaching.com/media/file/62475519867.pdfIn PDF document text
    • http://mygiftltd.com/userfiles/file/13670670228.pdfIn PDF document text
    • http://cuacuonanbinh.com/userfiles/file/20347194313.pdfIn PDF document text
    • https://viadagio.be/userfiles/file/83719395859.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/vefupuwiz.pdfIn PDF document text
    • http://tienphat.vn/imagesflashupload/file/70211984988.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/baradosowegozipitozafe.pdfIn PDF document text
    • http://kdbelektrotechniek.nl/uploads/file/gidupanubawiregavubi.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/lupifapubinezikem.pdfIn PDF document text
    • http://x04ydivan.ru/userfiles/file/17053355651.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=ringtone+maker+software+for+pcPDF 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_off0000eebc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000106ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CE 18600 bytes
SHA-256: 883f6bac6d88828f52b573b28351c3ba1010b7db109c5070bf4d3403963b2f74
font_02_sfnt_off000136ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136EC 11000 bytes
SHA-256: 58b5561c55d77ba85df6eef9f207852af6305d1a1cc6feeeb90304d98f2e39ba