Malicious PDF — malware analysis report

Static analysis result for SHA-256 540ff0001ec0faef…

MALICIOUS

PDF

83.8 KB Created: 2021-06-13 16:24:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: b03ae71f68da2f98300795c60471fe4e SHA-1: 6fd36444f9411537d6216e04d1cce948cf9d903f SHA-256: 540ff0001ec0faef7045fb08a03e17e4460671d94928c62924bf1e01d6fe2c81
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to various websites, many of which appear to be compromised WordPress installations used for hosting malicious files. The document body, though heavily obfuscated, suggests a lure related to 'Android screen recorder with mic', likely to trick users into clicking the embedded malicious links. The ML classifier and ClamAV detection strongly indicate malicious intent.

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://catamma.ru/uplcv?utm_term=android+screen+recorder+with+mic PDF link annotation
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/697a4577eb07a6e64ea3d042c2d7d1be/55706131464.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160776c98bea66---75090620096.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/cpt9s9fqka2phtstrqkvde6tm5/xefujadobiwupuvidemefeb.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/1e4074a325d16792067be75c4e209ac5/tuwowamefeni.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c59883c368d---28401141557.pdfIn PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/c0f45d39843ebf41e13e64b962b253d1/gufij.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/87195539059.pdfIn PDF document text
    • https://roeveragri.ac.in/wp-content/plugins/super-forms/uploads/php/files/68a0539a1bee391c66e966f312a3ea44/37269185366.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/aee71abb79c5457c9e120b22cfbf5ae7/78946806920.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/bbj264h7ra1d8k0gq09mu0a82s/finadagas.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1c279934e---86737055441.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160c5e6eb2880a---48213615293.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c54b6f8f616---vujudenudemopugisomos.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/10a3a1d617c7b747978dcdfa413834f9/tamulufefovuvusek.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off00010a64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A64 5016 bytes
SHA-256: 781972f1c76e887d694ade1d33bccd614f3cf25936b64466519ef15f4f91d926
font_01_sfnt_off00011b61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B61 11568 bytes
SHA-256: faa649db1842687d719c84dedc0c0bf7bc4c217f244f0518e2882f8e07ab6646