Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7109b281f376e8b…

MALICIOUS

PDF

83.5 KB Created: 2021-09-17 10:16:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a6b00c87ddb66cb5feb592a30ab14f3a SHA-1: 7c6e6eed4611087936003df15f7a824ed5c97ab3 SHA-256: c7109b281f376e8b19c6187270a450412d9c9cf9085394fe81db086c56c02f93
96 Risk Score

Malware Insights

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

The PDF file was flagged by an ML classifier as malicious. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to lure users to potentially harmful websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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://archism.ru/uplcv?utm_term=what+makes+a+villager+a+stonemason PDF link annotation
    • https://insinkerator.us/images/uploaded/file/febezomulujepiwixowo.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/14502679127.pdfIn PDF document text
    • http://sziazsauto.com/uploads/files/gegodewepevinutuvoniko.pdfIn PDF document text
    • http://kreativitaet-stadlhofer.at/global/images/userfiles/file/98830833827.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/kujopadalepoziwipikisila.pdfIn PDF document text
    • https://merohamro.com/ckfinder/userfiles/files/51415630571.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/ac6t5coabp2phsupev5b94dfo3/90693374222.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///46134903360.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140cd66e8ee3---42368385297.pdfIn PDF document text
    • http://www.huntsvillepr.com/files/files/76404680044.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/dubasevebu.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613819808a5a1---34623813714.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/70650542139.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe7157e1ce---liferadugomino.pdfIn PDF document text
    • http://www.lircai.com/web/inline/file/18631584571.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210914095036392.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/bofukorexerekik.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/22930437561.pdfIn PDF document text
    • http://33podarka.ru/pictures/files/53133137634.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/2242400488.pdfIn PDF document text
    • https://tdemo.order-pro.com/ckfinder/userfiles/files/75360213353.pdfIn PDF document text
    • http://ecosdaliberdade.com/ckfinder/userfiles/files/fegixefa.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/ede9c806eba57c2bb2c71330efa13dd7/50904018049.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/85g2ulrjnmspugarcsvq44t759/podugogonilen.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/64875014325.pdfIn PDF document text
    • 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_off0000e07f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE07F 10704 bytes
SHA-256: 1c2dca5fcfa7917b7532eb5e8807161a6b18725840532f0b68e23f536eb1ca5b
font_01_sfnt_off0000f8e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E7 17912 bytes
SHA-256: aad4ae7654311f67438cb17c3d795b82f2fcd51dcf285424bbef41ba51d3d595
font_02_sfnt_off000127d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1