Malicious PDF — malware analysis report

Static analysis result for SHA-256 5823b60283a3b03c…

MALICIOUS

PDF

74.0 KB Created: 2021-09-07 23:50:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 10417109ae1430dfb99de56c250d40ef SHA-1: 83b5aee428dd40d550669078142f067ec2a58caa SHA-256: 5823b60283a3b03cb5870cafca8f8fd0e9108d8e763dc04d3efc8879cc2e8c74
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites. The presence of external URIs and the nature of the heuristics suggest the PDF is designed to redirect users to malicious or phishing content, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ketchas.ru/uplcv?utm_term=pltw+engineering+notebook+pdf PDF link annotation
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2c415414cd---2599738144.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16093723be678e---76197821663.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/galamatapixafitabijulijov.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/0cb524e1a6aa5354464aa476e50acdc0/32920092534.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/pikogunerebajoludenemare.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae1d1a663d2---kidawuwosadiwujedaxujuse.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/7407366791.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160fc0f0db5522---27550797680.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/pexibutitelafagisasuvike.pdfIn PDF document text
    • http://melinterior.ru/userfiles/files/8970518125.pdfIn PDF document text
    • https://biovuspharma.net/userfiles/files/vexolalu.pdfIn PDF document text
    • http://k-souz.com/userfiles/file/kofajowetes.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/fsdavgom4utqg40n7q9nfrdfm0/19568737182.pdfIn PDF document text
    • http://ibrahimalsada.com/pics/file/66007583950.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a82543a4f9e---lexuserawuxalupapesisosi.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/pujufoso.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607766ec28afc---26597534629.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/17172306399.pdfIn PDF document text
    • https://yaofangpeixun.com/upload/files/xibenovonipoxolijajituwid.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/52158859610.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/75785552225.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/f365428de8784f101d579b437d1a5b51/sesukotonimud.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3f98a8292---60649358034.pdfIn PDF document text
    • http://parentini.it/userfiles/files/21865160826.pdfIn PDF document text
    • http://iccjsc.com/images/uploads/files/60264400292.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_off0000bf9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d7b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B2 10660 bytes
SHA-256: b9167372d1fb34d2b5ef3d2f57aa01ac628f78b1a3878ee03c89fbc2e3df45d5
font_02_sfnt_off0000efd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD1 16508 bytes
SHA-256: fe7500ea0defaab24ecef5cb8ef642d10f7074dac6cb7f3383c1a5fdc24c18d7