Malicious PDF — malware analysis report

Static analysis result for SHA-256 3338d498e276c74e…

MALICIOUS

PDF

88.4 KB Created: 2021-09-08 01:47:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7f8a5f8c86c2b1c847adb8b16c04f59f SHA-1: 62bd0821ae2a3daf10e7fd3dc7e3bc9bc372225b SHA-256: 3338d498e276c74e1b551abba79739ca6fa93ae0c28ac977e2283286805b107f
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to compromised CMS upload storage, indicating a potential distribution point for malicious content or SEO manipulation. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the structure suggests it's designed to redirect users through a series of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611c19cbee655---16571036933.pdf In PDF document text
    • http://soupworld.de/upload/file/46000256419.pdfIn PDF document text
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/tekufupazonewafo.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afd0eaeebe5---wokujoragijeb.pdfIn PDF document text
    • http://minerva-collection.net/files/files/modosimoli.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/01gtcn5k74pucg4b1gutk09aj6/14403183586.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210907_153259.pdfIn PDF document text
    • http://universalestetic.com/userfiles/file/88645248173.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/53139008870.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/h1bcq2c4t2sag8gronb019r5l2/wosefuniduf.pdfIn PDF document text
    • http://vtvxm.vn/userfiles/file/3894808131.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b06c6d31ec---sorejiviwebifoxezomiv.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e80513211---dodimabozejejibaluvexuki.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/27320811421.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/52824288543.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/aa4f9d9bdf9a22f137d92f80a45dbfc0/80571153065.pdfIn PDF document text
    • https://tekmaker.com/upload/files/23955192319.pdfIn PDF document text
    • http://3xlove.com/uploadfile/file/72419513020.pdfIn PDF document text
    • http://feach.ie/images/uploads/file/varupemebusoserafimirof.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/74387550550.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/c441c58c81f274f0d20d4b4e3f6dfaa5/26804250262.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/lewej.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/2679533480.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/7pipcus5napdmscd9qc4m689u4/34759236541.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=guion+teatral+de+la+cenicienta+pdfPDF 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_off0000f1ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000109be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109BE 19836 bytes
SHA-256: 615c4eaa49c9d2edbf232d992e834fa0645c7835bc162f7d0b26fbaa0c05d1b2
font_02_sfnt_off00013b7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B7F 10584 bytes
SHA-256: a5790fac8c7eede6d47cf9da053d50179328c0c03801362cea3cab7c0594dc4a