Malicious PDF — malware analysis report

Static analysis result for SHA-256 2aa738649a320088…

MALICIOUS

PDF

76.9 KB Created: 2021-06-12 09:42:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: ab34200e7bb168e5a4657448af069a16 SHA-1: 1af75bb0e95a7098e3e6f6ac142378d3720a2f85 SHA-256: 2aa738649a320088a5ae4ed65cbf96fca5ebaa7a674f0ef168db8e4af545ee70
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate it contains a link farm pointing to compromised WordPress sites, likely serving malicious PDFs. The ML classifier also strongly indicated maliciousness. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest the PDF is designed to redirect users to malicious content, potentially for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=the+core+competence+of+the+corporation+pdf PDF link annotation
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/e2e58374398b72902224f2dc0824d55b/noburupakixuj.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/052dadcac6ca6ffd871e69b4941f14ce/newevitawekiwovupigawekad.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4a80a6f14---2332338364.pdfIn PDF document text
    • http://ergo-logo-bamberg.de/userfiles/file/sogumido.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9f5446252---64273812883.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/cq18ff95jl8kj9lkvmcg163172/ginifagugavegudevababa.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/a1hqlj753lrr05d4sf6m401qen/84089120987.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/34561043928.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-19/20210519012445480031.pdfIn PDF document text
    • http://cortabellanews.com/userimages/monikitivuxuv.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a4cbede4caa---wufiporozugalewer.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607761b02d029---45987844555.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/pvdlc6r9ehsft7pk9mosjqfr1h/79693930484.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/46666591977.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e6bbe4f960---44184897385.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/d66a83a5e5697c6fb91ec90f159d94d3/57200961434.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/2a7175df57c478e9758816bf2f530362/napebatazenajigomugi.pdfIn PDF document text
    • 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_off0000ef7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF7F 5136 bytes
SHA-256: 437ccaa791c928526e67a04e6e5a3cb054f5a6cee975835e0dbae49f39695555
font_01_sfnt_off000100ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CE 10496 bytes
SHA-256: 4996ca414d0c6234ccbce238771ade0e7d7fdfc87b6cd53bb2a5453b656b3493