Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aefe95769ed1c0c…

MALICIOUS

PDF

69.9 KB Created: 2021-09-09 22:04:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d3658c4296d40326dbf5bbd50ecb9f5 SHA-1: bbf930ad4b44908d3e90c8e687f960fab7189884 SHA-256: 4aefe95769ed1c0c75722e38da71e0ed96d34828e7af3d85829930c97fd73584
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139a30eea8ed---mijabokiwinitomumetoxifox.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613316b4bea66---gisalibox.pdf
    • http://nscenter.cn/upload/files/57819223192.pdf
    • http://emekyesiltepe.net/images_upload/files/11206896542.pdf
    • https://12tiga.com/contents/files/pigonafodawopeme.pdf
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/sepusuzegawewuzosuwagu.pdf
    • http://xn--80aesyq.xn--p1acf/files/file/73208266136.pdf
    • http://aftp.bg/userfiles/file/dipazodeluraxozefefiwosug.pdf
    • http://koreabulk.net/userData/board/file/vogetojufixizevaboziga.pdf
    • http://www.leasebridge.com/CKUPimg/files/15168572622.pdf
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/74779855214.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16130c27803cc1---58956833373.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/rj1vvsmpdrtbo7ej0ugu0i6pkv/gudojadodizirerirozof.pdf
    • https://hargagila.com/uploads/image/files/37780670222.pdf
    • http://cachnhietwin.com/luutru/files/21454883909.pdf
    • http://joyearland.com/ckfinder/userfiles/files/xilopegumodem.pdf
    • http://www.chp.pl/ckfinder/userfiles/files/jasafox.pdf
    • http://dellalontra.it/userfiles/files/pofoguximolarikixesoviw.pdf
    • http://djapm.com/userfiles/file/kegiruzijukuwareromokujo.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/161383a15e9391---bunogamobaparizo.pdf
    • http://ig-einheitsloks.de/medien/file/xajuwiwafezolidux.pdf
    • http://www.iciparis.ru/ckfinder/userfiles/files/jedomijafikisoji.pdf
    • http://hyundainhapkhau.net/upload/files/33211702795.pdf
    • https://maviet.vn/upload/files/145664610.pdf
    • https://stotex.rs/files/nanexubunawosagolu.pdf
    • http://asid.rw/userfiles/file/ronibisozit.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=blank+character+copy+paste
    • 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_off0000b248.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB248 16792 bytes
font_01_sfnt_off0000ca5f.bin
6c75cacd2e076a796cfbe1609e4760b8ae8a13034bcf8887b98593e8ee3c2f19
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA5F 10640 bytes
font_02_sfnt_off0000e2c5.bin
d8c4a3f9eb104da2bdcd0ba26a65b1b2fa599bf0d2925c65fc8dece3e98780c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C5 15480 bytes