Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b700d6a1a76c7a3…

MALICIOUS

PDF

108.3 KB Created: 2021-05-25 20:03:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 1ee6a831d28b6a73401a16cc837a9445 SHA-1: 4ffd731dea9d4110bd2e2b2785ab3f7c061da7a1 SHA-256: 6b700d6a1a76c7a3242cb831fddbf6ce4b1256824e539dba0671d4f33488eeaa
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, which in turn host other PDFs. This suggests a multi-stage attack where the initial PDF serves as a lure to download further malicious content. The ML classifier strongly indicates maliciousness, and the structure of the PDF with multiple external links supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/2289cbf9f5de6955409e250d99a4351f/gaxutuwedivude.pdf In PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8f4d5cc29---bavomijisakekov.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/1debecc870f1a47e0a7feb1f2099a3ba/sugutas.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/8maq06ittmae7i528cbratjk32/fidufazavirokidotisoduje.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160832f5a662df---84382909886.pdfIn PDF document text
    • https://brahmagnanam.org/fck_uploads/file/mewugimekaguvu.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/b8bkdp8q8ivehtc3582pvpvu5m/63392424848.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/4efb3029e9c709ed484591de4190acfb/kaneminanivupega.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/file/14691972388.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/032249225222.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609884056af1f---wamexawoxamu.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/migigedemibupa.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606c691aec608---95980182939.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/67511013548.pdfIn PDF document text
    • http://sugarfree-gelato.com/upload/file/31657794111.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=arbitre+sp%25C3%25A9cial+wwe+2k19PDF 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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off000182b0.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x182B0 19224 bytes
SHA-256: 6505788d70acc48a16769bd3c3b21a6a7f03906ad59852884afc57390e1ed979
font_00_sfnt_off00013bac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BAC 5692 bytes
SHA-256: ea95c558cb543d6091dcc9aea8c4df61384d24c112e10b5cf298e578d9f03b02
font_01_sfnt_off00014ee8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EE8 18012 bytes
SHA-256: 6f16ace04f29ef50622abaebc878e16c3fd630ad16907976b37c4487ca566e28