Malicious PDF — malware analysis report

Static analysis result for SHA-256 a923fa870d3e6f0e…

MALICIOUS

PDF

71.0 KB Created: 2021-09-22 16:19:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2f50d5b96f90327eedbf6d124d720bab SHA-1: 805c2eff2cf0617d60de47f847d1fb6cfdbc2697 SHA-256: a923fa870d3e6f0e7197db6d71b91f88d20b4421c5b74e17f86115e31355486c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these URLs and the overall structure indicate an attempt to lure users to phishing or scam pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://chcial.ru/uplcv?utm_term=antutu+benchmark+note+9s PDF link annotation
    • http://fuerst-architects.com/uploads/file/14156397270.pdfIn PDF document text
    • http://contrast.no/ckfinder/userfiles/files/35577235248.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/gulizipitanipumudevodurit.pdfIn PDF document text
    • http://vce34.ru/attachments/file/jiritobi.pdfIn PDF document text
    • http://quaretti.it/userfiles/files/23312782251.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136d8eddfd6a---bowunerej.pdfIn PDF document text
    • http://avon-bratislava.com/files/files/pibinilofusamobuzewuse.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614658ebeb3ea---15854254095.pdfIn PDF document text
    • http://tongrentangthai.com/UserFiles/file/jujad.pdfIn PDF document text
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/tenifukenelobomomafulim.pdfIn PDF document text
    • http://matsonconstruction.net/userfiles/file/72189515715.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/59980898049.pdfIn PDF document text
    • https://luiginoiobbi.com/userfiles/file/10181135589.pdfIn PDF document text
    • https://3rproject.eu/ckfinder/userfiles/files/92206279812.pdfIn PDF document text
    • http://staresecurity.com/userfiles/file/dorukebuzukulotamufodux.pdfIn PDF document text
    • https://h1t-urlaurora1-turbo.com/contents/files/sebijipufof.pdfIn PDF document text
    • https://vroa.pl/chplusfiles/file/77607612273.pdfIn PDF document text
    • https://go2germany.ru/files/file/97213455273.pdfIn PDF document text
    • http://healingtown.org/userData/board/file/vofuvak.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/4318cf75fce1b18c194788230b585c8a/xupezofibujipu.pdfIn PDF document text
    • https://dampinggame.com/calisma2/files/uploads/21564586095.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/gabozogetotuzarevizixugu.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://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_off0000b0a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0A3 17308 bytes
SHA-256: 0efd9fefb9d54ef54731c9bdc6a15395ea32fd7405265ae35b8589e04f3248d8
font_01_sfnt_off0000dd6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6B 10836 bytes
SHA-256: 1c57b45c3c20b99ca9d4735e3e12a5a4abed62fb52902fa0798a8167564f069f
font_02_sfnt_off0000f657.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF657 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1