Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4f64d2bba722965…

MALICIOUS

PDF

65.6 KB Created: 2021-06-22 16:37:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: faed217c667be5f9426f2808f0c0c99e SHA-1: 0d39e4d61a40a7dbd1b14063b03b14c09f7ae9c1 SHA-256: b4f64d2bba7229655bcceaecad862742e9dd609c06e0abd2bdaf3dc1e48f2a0e
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074474f35f24---34088982588.pdf In PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16093ce3500437---86552627855.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/xewijabanozaxusa.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/e79106565b2b9a7b359f87191f341847/genalujopereke.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160754f482ed17---kisexojivikezufov.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16091d3f89b305---93898422492.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/kcqgcjiufgr9ih509r7vfuj653/42610541285.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b4b9e3312c2---33482446480.pdfIn PDF document text
    • http://riph.pl/userfiles/file/pukopujotatubiboruwagudu.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/4e190e4c4d1d9ce8bb3db44fce3281b9/zikuvulumodimeninamuwonu.pdfIn PDF document text
    • http://abpaluso.com/upload/file/47098296503.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc95e1e382---najeleruzut.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083828694aca---vonupujuk.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e59700c6e2---46257535367.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad28c459b1---vifevarizos.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160946c4d0a732---70472760503.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/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=vance+walberg+pressPDF 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_off0000be61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE61 5296 bytes
SHA-256: 3155b140eedf6fc6de0fb5fc475b4ab685d559727cf5f2462a00e94521f8b77a
font_01_sfnt_off0000d08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD08A 12052 bytes
SHA-256: 3258432bf1c210c323870b0e889ddc0d1372916ace9c6219014c52b4124b37cb