Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ddf2a7652ffc441…

MALICIOUS

PDF

81.6 KB Created: 2021-09-17 04:02:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f6fbef5893ecc210b972bfd62c126dc8 SHA-1: 1df691c6982eb30576fe182c208787d9183a1919 SHA-256: 4ddf2a7652ffc441d03be504f4142250f4d30a4b0319d72f29454f2d9dbb9e81
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to external PDF files hosted on various domains, many of which appear to be compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and link farm suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://kag.fr/userfiles/file/nilivilujepavanipo.pdf In PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/i0udb5i22qmm2kcd5ienjl80hc/wilidetat.pdfIn PDF document text
    • https://ipic.vn/userfiles/file/jadavadubazudoje.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/xuvidigi.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-9-17/20210917060224536541.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/87745927311.pdfIn PDF document text
    • https://ourlady-schools2.com/userfiles/files/91510670068.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/4432280474.pdfIn PDF document text
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/74360677287.pdfIn PDF document text
    • http://ms-domino.eu/images/file/files/pakowigidaxofate.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/d352e164947a5f2da771fced608a026f/xamuzenololajokikala.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16143d185292d6---galimobevive.pdfIn PDF document text
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/89232481245.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/52800608565.pdfIn PDF document text
    • http://sumisaedu.com/FileData/ckfinder/files/20210901_59884D0B7DB078E8.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/6cef843ac2e0c04f3cf7d146d2019578/murulizowujabenires.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/mei9uuvfqds13r1315treo0ji5/kevivevomebogebexowam.pdfIn PDF document text
    • http://hasicimosnov.cz/foto/Image/file/kuwofasewikikuzinab.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/xunonojufipa.pdfIn PDF document text
    • http://kietminhrivet.com/upload/files/33009302385.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=modern+combat+4+mod+apk+free+downloadPDF 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_off0000dadf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDADF 17272 bytes
SHA-256: 63adfa8355216fcc477e910ab408b12c9c9525d61096770d1c5807d331af4ba8
font_01_sfnt_off00010768.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10768 10908 bytes
SHA-256: a6db4b2074ca96be7b6450ac5c615f7ac0b0efcaaa8602ed9dfcd562834f6691
font_02_sfnt_off00012089.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12089 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1