Malicious PDF — malware analysis report

Static analysis result for SHA-256 df92f7a779746828…

MALICIOUS

PDF

72.8 KB Created: 2021-09-11 18:33:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: f4e130293e6313b3974800babc3dea32 SHA-1: ad7c0952ce0a58ad426717b5e275e714c3e9c371 SHA-256: df92f7a7797468283f808e34a03be39bb4fae44bab84a17832678cbcee5e7926
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites and other disposable hosting, indicating an attempt to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were directly extracted, the structure and URL patterns are consistent with a malicious PDF designed to lure users to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://etoprosto.ru/ckfinder/userfiles/files/64253701669.pdf In PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/84402220768.pdfIn PDF document text
    • http://abwalabamaave.com/uploads/files/50436377831.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137c5f34b379---48013389280.pdfIn PDF document text
    • http://toanlinh.vn/upload/files/47241312543.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/sejekuxulujotavusakax.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/eh07eu6vrq60brj9kj0n860oo5/lemolumu.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/78233801892.pdfIn PDF document text
    • http://asclyziarskyklub.sk/userfiles/file/werebepuwema.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/46657122615.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/kimemal.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/98481025329.pdfIn PDF document text
    • https://jeevandeepspecialcare.com/ckeditor/ckfinder/userfiles/files/fagojudeji.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/sugofelujekebogugopadajow.pdfIn PDF document text
    • https://yuvasarkar.org/userfiles/file/81854206548.pdfIn PDF document text
    • http://uzks.hr/upload/datoteke/32525938837.pdfIn PDF document text
    • http://sevgineslianaokulu.com/ckfinder/core/connector/php/uploads/files/bugojir.pdfIn PDF document text
    • http://cwesp.biz/upload/file/6878846109.pdfIn PDF document text
    • http://scsychem.com/upload/files/gisamikipabudojonafa.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f039815bc---76023001442.pdfIn PDF document text
    • http://crystaltrade.hu/data/file/609440053.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/bezebojazakugevuwovi.pdfIn PDF document text
    • http://gpmpoolandspa.com/ckfinder/userfiles/files/21840492595.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=manufacturing+date+of+my+phonePDF 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_off0000b91d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB91D 11060 bytes
SHA-256: 7f43741d173f90997467bc71769d15b65273f9171727370f9c9f206ed93859f4
font_01_sfnt_off0000d27d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD27D 16816 bytes
SHA-256: c2d96d4d35ae2ce30205c78bb360a5dfbe7192b37b1499adca9bacc0d64dc49c
font_02_sfnt_off0000fd9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD9E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1