Malicious PDF — malware analysis report

Static analysis result for SHA-256 28bd378c168a9da9…

MALICIOUS

PDF

71.6 KB Created: 2021-09-30 11:35:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7737352a7ed05eef51ed87b1072fc6ae SHA-1: 73f932cdad566320f39651dec85fd992b0cb722b SHA-256: 28bd378c168a9da99673c41da7a10d3c660a007a551ba244b1002ff67d9d522f
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links indicates an attempt to redirect the user to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/dtl51q74541lt88oltfs4vr9rg/kiwutumagixedupo.pdf
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/xotipadasizesebopexewi.pdf
    • http://anm-av.de/uploads/files/wuxarofaxanaleko.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/b3258a6f0c63d70082af6eb82b01cb6e/35434961898.pdf
    • http://tcsm62.org/uploads/news/file/8940256207.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d7534bb9d---bozajit.pdf
    • http://orderleesushi.com/uploads/files/44035872645.pdf
    • http://eszixv.hu/ckfinder/userfiles/files/resibudukifalunowufifoju.pdf
    • https://trvstore.com/userfiles/file/fuzumemedunukepodo.pdf
    • http://wajl.net/img/file/20219802358.pdf
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148354443658---tafagomorol.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16133d5c2a03f2---kikuza.pdf
    • https://h16hr15k-h19hr37urn.com/contents/files/zejidinanub.pdf
    • https://getadoc.in/ckfinder/userfiles/files/85664122413.pdf
    • https://bunianco.com/other_files/File/konazisaxa.pdf
    • http://alnadaoil.com/userfiles/file/99301470790.pdf
    • http://dlzj.net/upload/files/20210929180749184763.pdf
    • https://cplastik.cz/data/cms/file/56306662379.pdf
    • http://xn--80aafkatcapceshpicpg3h.xn--p1ai/pict/file/wesatijepibubepizavif.pdf
    • http://sicilalluminio.it/userfiles/files/kalukuvobalisidekide.pdf
    • http://musicpark-live.com/userfiles/file/jaguwevopiwiwofaz.pdf
    • http://cokhihoangvinh.com/uploads/userfiles/file/vegoregamudenerasuxemuw.pdf
    • http://protok.pro/upload/files/95094671181.pdf
    • https://hotelexpert.ro/uploads/files/budofi.pdf
    • https://autosaloncenter.com/uploads/file/54237490421.pdf
    • http://kdekdyjak.cz/data/353416049.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=global+offensive+mobile+apk
    • 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_off0000b3ad.bin
c4dff4230540b69433ef8b4ac3051d628eb52b07d280d53a2fb35879aa5bb4f4
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3AD 10660 bytes
font_01_sfnt_off0000cbe9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE9 16792 bytes
font_02_sfnt_off0000e3fb.bin
74bc42ed9b9a80c979472b9aa6909ad5fdc39f6b08ee764de043ea89f7984b6c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3FB 17684 bytes