Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cb38e48d8818ff1…

MALICIOUS

PDF

83.4 KB Created: 2021-06-26 08:09:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9adfda544f26103153df227bf559910 SHA-1: 429ad9a9d9d17bc9949972eb6b0012053ed721cb SHA-256: 4cb38e48d8818ff14323ef59d3504dbf9af4303493abeeb515ab3fe4d2c41aa8
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to numerous compromised WordPress upload directories and other disposable hosting sites. This pattern is indicative of a phishing or malware distribution campaign, where the document itself serves as a lure to external malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://elitstroycraft.ru/source/file/pilefenonofofogurotokenep.pdf
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/5216809711450a4dd1c6efdebd315286/sefabofanisemem.pdf
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/16d0cddd0e019123839c4fcf693892ca/5046886118.pdf
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/vej76grr3op6lllg8tafm0mpi3/xopuna.pdf
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/24ec0a2f2beaff3ba9b177ad006387c3/98686959065.pdf
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160812649503be---1921826610.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca33018e61---30508376290.pdf
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c8fcb6554---46926842787.pdf
    • http://haithuanphat.com/uploads/files/sifoxubarajekuve.pdf
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/qesi1v0h6cp4v3nabhb72kq1c5/vesuruk.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079290e5e644---gukek.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/k51hckslg7per05e4cp7bmlpf7/48569360545.pdf
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/e32e9a98f8d663c9998147c57eb55ddf/devosekebi.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d690a70442---56900264942.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c500260a8---kinugakubogomipok.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab41e881c37---6450374097.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607619d5cc045---96377682690.pdf
    • http://wallsfamilyreunion.com/clients/876683/File/jegasuzunijekud.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/08e0b6546e818540adfafa9a966c527c/3104721145.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/d5kthfnitm65kilug550injpo1/13816792447.pdf
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cce0f9a9bcb---dadepekefosidevosedo.pdf
    • https://kitapkaplama.com/upload/ckfinder/files/47725294658.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd0b6615b1---63206273568.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/c94692aa4e742852a31b1eea150a07bf/69369165642.pdf
    • https://atraba-holding.com/userfiles/file/bagitafuwedoliwon.pdf
    • https://werbemittelag.chupload/file/befobulagenonuvolag.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=physically+challenged+people
    • 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_off0000e1ba.bin
d0fdb173b2e0d5301828073126c18cb426a88654986e2a8c65c08a63582aa894
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1BA 17708 bytes
font_01_sfnt_off00010ffe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FFE 16792 bytes
font_02_sfnt_off00012815.bin
1264c08c9dfd02e435011da56bf355eccf5a82fb7daa0462bd473c35c7c4930e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12815 10712 bytes