Malicious PDF — malware analysis report

Static analysis result for SHA-256 efdf0eb21f3f3483…

MALICIOUS

PDF

85.7 KB Created: 2021-07-05 11:28:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0308cacf8b8f6e0da4cbe65a4b2ddedf SHA-1: f6ef87ddbbd8bbd73d1f6eb973c03900ca59176f SHA-256: efdf0eb21f3f3483dfe36a1bef503261dc36d8e01060bebaae89a5f89957a0ee
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 links, many pointing to compromised WordPress upload directories, suggesting it functions as a link farm designed to redirect users to potentially malicious content. The presence of external URIs and link farm heuristics indicates an attempt to lead users away from the document to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://larioenergy.net/uploads/file/78327335972.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/4j9igv807tevnb3142vdc37ka6/55328065552.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe3df04cc3---jufupologilomumaj.pdf
    • http://thamdinhgiadaiquang.com/img/files/veloz.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090b7e17213e---81689243523.pdf
    • http://alkanboya.com/files/file///59848560174.pdf
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/imqdmvj6q4skshuiu402o2cq1k/82759365946.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160701bb0cdfa4---lizosexuremu.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985d74738ee---suvigemewibofu.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2db40c3a2---67243295512.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/j6t2m44cc73smkgenudue4bh0l/nupudoxumajenov.pdf
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/a8db2b4d7da65df66908d52eeedb0cc0/zudefawuwosimexogulofofok.pdf
    • http://beijingxinzhi.com/userfiles/file/20210511102231_324328018.pdf
    • http://bomtvplus.com/data/board/file/20210512112543.pdf
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/3sushq9eta7thtg2l6cej1hee9/32064438105.pdf
    • https://hiampelectric.com/wp-content/plugins/super-forms/uploads/php/files/5050222c24fdc7063906403534732400/xitemobalekala.pdf
    • https://apz-arte.com/ckfinder/userfiles/files/rakigazoxewigudo.pdf
    • http://asijskepotraviny.cz/files/file/jeranad.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/c0d848655de2c238b7ef2757945ebea2/weparatas.pdf
    • https://bselink.com/userfiles/file/xesuwimurekatasilex.pdf
    • http://hoteldarim.ir/basefile/hoteldarimir/files/97982384202.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a04e7f6e772---kodutavakiwigoxokuwuba.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/1608405498bd86---wezeva.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=everyone+is+an+atheist
    • 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_off0000eca6.bin
7aca791e3b5ad489cb9167178735ccf753b24696bb9ef53461da4b7af67de42f
pdf-font-stream PDF embedded font (sfnt) at offset 0xECA6 17508 bytes
font_01_sfnt_off00011a4b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4B 16792 bytes
font_02_sfnt_off00013262.bin
eb4cc39869b8f298a4528d522b7683a3aa06fa9528998b55bc3f5b7f624d0fd6
pdf-font-stream PDF embedded font (sfnt) at offset 0x13262 10324 bytes