Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4ead1e2bbee44e2…

MALICIOUS

PDF

80.6 KB Created: 2021-07-23 04:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5cef8140b9dc02c9177e587a1eff6e0d SHA-1: 89d98e34df8d88fc05763e4c933e387ef4c62094 SHA-256: a4ead1e2bbee44e273e0e899afb0d6392580f09d67ae9c9b757f9c467b654c3c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, so the primary attack vector appears to be the embedded URLs leading to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://agataklimowska.pl/userfiles/file/dezajejezogenatik.pdf In PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/16078303b4d529---23726371812.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/90aff1603e994a25451962844dba5941/jijelijisufazida.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/bce095702f0edf4fb9b714d568b888ac/ximozakuzedetit.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072b7ed5b60a---90216794924.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/ec04e2a097c8d5ce8e56c08d72d67b40/zorenawifulum.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160ba1205cdb27---43846740798.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/xetuworejol.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/22347624285.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/ad38bbed3b5a78ebfc00fe344b68b0f5/46369184959.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aa507de53a---50640455928.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/32484077134.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606db57951ef0---86681062568.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/kojamapin.pdfIn PDF document text
    • http://hz-karavany.cz/ckfinder/userfiles/files/pisetidimowu.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b06e34753---dofanamoxufijazudapimaw.pdfIn PDF document text
    • http://bud-drog.pl/userfiles/file/parewopur.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/39237291377.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/11459647581.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4f70f32ecd---43641129020.pdfIn PDF document text
    • http://location-venise.com/italie_documents/files/88366856977.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/73635918420.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9641989495---50145141370.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cccaa013eb---povulotidobopej.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c57b3a6de1---21218036821.pdfIn PDF document text
    • https://waroproject.com/file/zamakopajafimonu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=use+nand+gate+to+make+orPDF 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AF 10552 bytes
SHA-256: 534f1182acd95316024ce458759d2c4c33450f9d91126813b9c72bfd3a108218
font_01_sfnt_off0000f085.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF085 16980 bytes
SHA-256: 8b93e85b5a022adcda7119803e969ae7bcd6cb9c131a327331c7d3d330d29d06
font_02_sfnt_off00011c6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1