Malicious PDF — malware analysis report

Static analysis result for SHA-256 8137279deae2c321…

MALICIOUS

PDF

81.9 KB Created: 2021-05-21 19:31:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: c1bb15c8cb8af51dfcaf8792790fff9d SHA-1: 7e6a2b118e37dd926be0df20b22f4c2c56f98b7d SHA-256: 8137279deae2c3215d9b21a5b8d0a2be382584fcdf67b8b9dc2f67ad884b52c4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, specifically flagged as Pdf.Phishing.Trojan. Heuristic analysis revealed it functions as a link farm, with numerous URLs pointing to compromised WordPress installations and disposable hosting. These links likely serve as lures for phishing attacks or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a61a50dbbd6---65045972655.pdf In PDF document text
    • https://zlatartopalovic.rs//files/65048824381.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160920b6e461d3---xukuvuxoraruganu.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/wekujuzubopazod.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a4fa5430524---fujirufepir.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a6443400682---sajibujidirujolu.pdfIn PDF document text
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/69fc05fefbd660288b451b9bc78acb08/79276554619.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/25654246735.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/8356ded98a74fbf72c0e85b3b11277ad/83724071559.pdfIn PDF document text
    • https://www.analfissur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077bb0fad8e2---87654082445.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a29d580a234---22577235724.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/0d6ea0e468fda2d49217993dc3279737/biluxuka.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/678366dcf8d7b2fd1bc4f9aa77cf6829/15204042468.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/0f5448ab06a6f4577b8af92b38a4c4af/sisejibexinegatefapaf.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aa907bc929---52854492143.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=delta+type+p+shower+cartridge+removalPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010325.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10325 5740 bytes
SHA-256: 971b7a6d4f23ea2f9b506e2196a85939d5c499756dbb5bbc9ee34db804129dd8
font_01_sfnt_off000116ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116AB 10608 bytes
SHA-256: 8270b73223cd2a989aa0c9780f13ce15e8a6f621ad0d96f79b595341ea3c6016