Malicious PDF — malware analysis report

Static analysis result for SHA-256 51a29f23676cbe72…

MALICIOUS

PDF

73.7 KB Created: 2021-06-17 22:22:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 32c271412b5b962c1b6397848d882dca SHA-1: 8e13eca8bd9c0ab387c5359a63f88273ffdd7f6d SHA-256: 51a29f23676cbe729a82aee12a4a6fb2e576675b8303aa9e3b5687f835add48e
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains a link farm pointing to various websites, many of which appear to be compromised CMS uploads. The document body, though heavily obfuscated, suggests a lure for 'mp3 songs download'. The ML classifier strongly flagged this PDF as malicious, indicating a high probability of malicious intent. No scripts were extracted, but the presence of numerous external links suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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 http://transinfosoft.com/userfiles/file/duzojomejelugiritazar.pdf In PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16081660ff3533---26978956774.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/jscnafs1cjcvri59njp1a5abe7/93296482402.pdfIn PDF document text
    • http://iltorg.ru/upload/file/mukatavurixezejotewe.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16088f234c9f39---38108379170.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20210605132254.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/94162556317.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/33017096281.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/86194cf691a6ed9b732006ed55f957a6/dawanerunabuwanivuzad.pdfIn PDF document text
    • https://xn--80aaijzh9b.xn--90ae/documents/file/pufar.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5a1bf01f0---lobogirawiwiwixojoxututil.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4939ec5ddc---21046156067.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a199ba1a87b---12030747759.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c346845775b---85906792094.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/naloxofogovemaja.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/31303471c4b400d2fe19ec49d3cf9204/zosixikikulerinevuzu.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160773210acff0---44239457031.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=let+me+love+mp3+songs+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE231 5440 bytes
SHA-256: a3ecfc063465d83e90d6b9d2f74fc61cbcc00a5575301ec1b536c6f1982e95b6
font_01_sfnt_off0000f4ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BA 10888 bytes
SHA-256: a8725b5346c517fa94edc3f608ae960d343eb493a01b8b992039a69184ef356b