Malicious PDF — malware analysis report

Static analysis result for SHA-256 7dfdd34863efd9c0…

MALICIOUS

PDF

75.2 KB Created: 2021-09-13 02:04:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3f97a3999459075b5f7c22517a796ccf SHA-1: c85bf32dce072702c3e5f4bc55be9cad55e4ebe9 SHA-256: 7dfdd34863efd9c05b660ff1b250f68c2e9913892f340be76dfab3cccb7d63ef
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to domains identified as compromised CMS upload storage or disposable hosting. The ML classifier strongly indicates maliciousness, and the link farm pattern suggests an attempt to drive traffic to potentially malicious sites, possibly for phishing or malware distribution. No scripts were extracted, but the overall structure and heuristic firings point to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://songod.vn/uploads/image/files/19372568625.pdf In PDF document text
    • http://bfcy88.com/uploads/files/79407516529.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210903012326.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/ganev.pdfIn PDF document text
    • http://africareview.in/userfiles/file/671665077.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132b3a378dd0---rasubep.pdfIn PDF document text
    • https://crc.creativechange.net/ckfinder/userfiles/files/54011753432.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/6338b71mn6oh76tgn7d8idgo7d/tizerebezuxefuxuxizedoja.pdfIn PDF document text
    • https://frutalmente.pt/site/upload/file/zimonido.pdfIn PDF document text
    • http://eko-baby.ru/userfiles/file/dokelewijizasawajevasav.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/dijasugafoja.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/ritodaziputonutewexesi.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/95290394405.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/s7jvcr4aok4p87lr8fduvh0ucr/37524262393.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613007424f1d8---50064658007.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/74519392929.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a0aeba91da---20616278769.pdfIn PDF document text
    • http://www.southpointinstitutehowrah.com/admin/uploads/file/58741792554.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/rotasakiga.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/cf39866d2adc1776d890f10d05124960/jugatonef.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/74122441318.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=animal+farm+chapter+7+characterization+worksheet+answersPDF 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_off0000c1e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1E8 16832 bytes
SHA-256: 246d5cef011d3c046a93f7bc374dbec6ab39a68e1c0dabe7a9da0a306046a0a5
font_01_sfnt_off0000ed24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001053b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1053B 11012 bytes
SHA-256: 2648bea28dd71b16681b0fd58ed7ea7927167e185f1f81e0a0e657e79ab2b100