Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a920c5d79f6c881…

MALICIOUS

PDF

74.9 KB Created: 2021-09-29 13:33:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: faea850c99a8d6d4e23621efe211e994 SHA-1: 94e4a6ea9a9f9f7aa6caaa7b317779640938c180 SHA-256: 0a920c5d79f6c8818d8613ff9cbdc18dd54cd3e23fa7aa8689141e56d03e8108
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to other PDF files hosted on various domains. Several heuristics indicate this is a link farm, with some links pointing to compromised CMS upload storage. The ML classifier also flagged this PDF as malicious, suggesting a high likelihood of malicious intent, such as SEO manipulation or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

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://funcarele.com/ckfinder/userfiles/files/pivasibalimizijeg.pdf In PDF document text
    • https://bk.knu.ac.kr/ckfinder/userfiles/files/jimezujaxikaves.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/78621938356.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/58921997661.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/22218503312.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/27341771379.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/nupixipivoka.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/solalododewuk.pdfIn PDF document text
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/vixudoziletituvedoparo.pdfIn PDF document text
    • https://moyaexpresss.com/ckfinder/userfiles/files/2034987110.pdfIn PDF document text
    • http://xn--2-140-swe8h.xn--p1ai/files/56107308961.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fffbfbfc35---jumitefaxuxilofuj.pdfIn PDF document text
    • http://1qjd.com/upload/files/2021-09-11-23-11-15-QIV4RSEU.pdfIn PDF document text
    • http://5percent-design-action.com/upload/users/files/14250595253.pdfIn PDF document text
    • http://studiogaleazzo.eu/userfiles/files/91943213324.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161476b344b893---ganel.pdfIn PDF document text
    • http://xn--b1adrijbbb.xn--p1ai/upload_picture/37895198364.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/gopinukepofetomuvanaz.pdfIn PDF document text
    • http://biosystech.com/pdsFck/file/rabusi.pdfIn PDF document text
    • https://creativenursery.net/home/creative/public_html/ckfinder/userfiles/files/29772993752.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614c2f052c537---kunopuxi.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/51f2fe703701a71ca6ac107bc5ec6178/59656889093.pdfIn PDF document text
    • https://store-connector.com/_upload_bilder/_filemanager/file/43299048604.pdfIn PDF document text
    • https://simbhaolipower.com/images/file/nazisewadegakev.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/77288581515.pdfIn PDF document text
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/livinebotefako.pdfIn PDF document text
    • http://belean.pl/userfiles/file/rabiputine.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=product+key+windows+8.1+installationPDF link annotation
    • 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_off0000bb01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB01 18700 bytes
SHA-256: ad4babb7f3125e6e2b7000b23c8939f5e362719f7d850f592aba11f28cf1cb49
font_01_sfnt_off0000eb31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB31 11080 bytes
SHA-256: c009733e25cfae7521480d63058e0a684dfe136a61f567f2a255f342286816b5
font_02_sfnt_off00010551.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10551 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1