Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b23fa4f98d408f6…

MALICIOUS

PDF

82.0 KB Created: 2021-08-10 21:00:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9cdf4115db1285ebf7d4e12223f672ba SHA-1: a683367b8436e1590650d91e1c7408b916ae4f76 SHA-256: 7b23fa4f98d408f60be0a2af813ef6e2d1fdf87c5fb707464d8e3aee2edbe885
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous links pointing to potentially compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it's designed to exploit users by directing them to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://irths.com/upload_files/files/3668975923.pdf In PDF document text
    • http://csc010.com/userfiles/file/20210623014629_btlogv.pdfIn PDF document text
    • http://eviljoy.com/UserFiles/File/fapananunomizidupixuxona.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/4684388463.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/116948dace2c3b35dc329ac266cd80fd/47524403629.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/0ab5952e1a8c21514f16db4e8360dc90/87090684775.pdfIn PDF document text
    • https://mimpiindah1.com/contents//files/gixelajigojukutogufewaf.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aff6c3df78c---40941292093.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/7465c4c1e49225266785becaf5e8f297/45264063615.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16083a8dce2e12---jikofot.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e166bf3a883---9963074498.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b65fd2ea89f---61164242455.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1045a8dd0---mojomerovokidekefi.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607224c9d005c---guvijuvaguvoxewixuzopivos.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/lixalil.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6636650f88---62830373832.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=elements+of+nonfiction+pdfPDF 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_off0000ddf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDF9 10500 bytes
SHA-256: 6bee388abd67617270a4bac57e332190263060c0e24533af4f4b50bb99cfc5e6
font_01_sfnt_off0000f5c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C9 17268 bytes
SHA-256: 70e87729c4faab8d667c742872e50ccbde5fd269efc6b1e1b3aee3c5ff5df34f
font_02_sfnt_off000122d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1