Malicious PDF — malware analysis report

Static analysis result for SHA-256 78f2c175a86b2f93…

MALICIOUS

PDF

65.2 KB Created: 2021-06-24 17:26:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 63736d0fe77172e1b3e2cd7d80878948 SHA-1: 457c687c09c4ec761ad797a4123251e6d7453f69 SHA-256: 78f2c175a86b2f93196ac60ffe4af1e9977dcc5a57690e8922eaa2ba77c91021
156 Risk Score

Malware Insights

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

The PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It leverages a link farm hosted on compromised WordPress sites and disposable domains to distribute further malicious content, disguised as a repair manual. The presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious sites for payload delivery.

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 http://oio.cn/uploadfiles/files/47135587826.pdf In PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/d11278dade7f98c416b94a4479591574/58014103666.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/16085c9b21235d---duxet.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/3acb460868a2781cf5745dd24a1c0f35/5176293864.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b010e4be85---3710454879.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/ina7d7lspecbpodpe9lk4ko3t1/27457653530.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/fokosazosi.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/19206940030.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/isof7ge9a0jk67go9ss2o87mv3/76285713615.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/425da0f482ab96ae81e8672b60c33941/boputiwugigure.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/4cacdd28bd45051807a88ca4dee686c7/86461538579.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/5cp1m7ko6ajvl02m567dtvkmp3/kadavomatumitazode.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/936f3718ab28bdcb311e95da4d5c1712/gufefuw.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160975b8ba51c4---52490125060.pdfIn PDF document text
    • http://sterkrade.net/ckfinder/userfiles/files/fijajisaboku.pdfIn PDF document text
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3f4967f2f---jupawozazigekiwidusu.pdfIn PDF document text
    • http://ruresept.ru/files/file/jevanomuzefevivitedozasa.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c43b50d1b4a---bosox.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/69338371328.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/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=fisher+paykel+dryer+repair+manualPDF 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_off0000c135.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC135 5320 bytes
SHA-256: d8f516ecb41faab9ef9f5029abf570a10617522194baf449efc35456581d2993
font_01_sfnt_off0000d32b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD32B 10836 bytes
SHA-256: 1f675af3cc621a430f052e6ef140ab2a2088b0df33851ef35809ce5296f53338