Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aa18a23d9d4095a…

MALICIOUS

PDF

84.6 KB Created: 2021-09-03 07:48:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 881ed827ec3ed06f385c00d466de9829 SHA-1: 6424439f1ed2c43d87953eec311083c09f7569ac SHA-256: 4aa18a23d9d4095a1c2a95d5a90d8105aa456da6e38e8bd02d9ad118816f06a5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous URLs pointing to compromised CMS upload directories, suggesting it's part of a link farm designed to redirect users to malicious sites. The presence of these links and the overall detection profile strongly suggest a phishing or malware distribution campaign.

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 https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/accd8afce14bcd9e79745b5d3bb00225/tazode.pdf In PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160c9c0a268114---99097217279.pdfIn PDF document text
    • https://gitteszoneklinik.dk/ckfinder/userfiles/files/narumuvawudu.pdfIn PDF document text
    • https://kuepancong.com/contents//files/78848952096.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071042682812---28787166476.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/7e8a2519afd289bb538c7f9424e99a1c/loxazojepu.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d6372517d13---3128168751.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a998b512fd---33059364300.pdfIn PDF document text
    • http://sensi-leszno.pl/userfiles/file/mikopi.pdfIn PDF document text
    • http://salon-urody-bellis.pl/images/file/xuzifikoforopi.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/665c965b0f5a4bfd00bc294fe344c1c6/rujovesumanotezodadariwo.pdfIn PDF document text
    • https://manenshop.com/upload/files/56438459847.pdfIn PDF document text
    • https://keepingscore.org/userfiles/file/busuvumodigesa.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9bfef0d73---womozuxokofuwijupejisimi.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/valopajobuk.pdfIn PDF document text
    • http://interno-kazan.ru/upload/files/40493223048.pdfIn PDF document text
    • http://calisnt.com/uploads/files/68909365044.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161146eca1e4dc---kolenoxinige.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f228a1752b---29094827461.pdfIn PDF document text
    • https://aquaprosmart.com/userfiles/files/pogokatokaseki.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/djs88rr2ujd62j6sa3v3nc9vj9/gafesabifusunupa.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611acd73b74e2---bowedezewuzusalolomo.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/002c85c8c18e8e417a5fd27d965610cb/misufe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=verbe+avoir+et+etre+exercices+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_off0000de53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE53 20784 bytes
SHA-256: c5d8eb4990749083d384861ee8aef47aef39f4eb7b3c893583b3f6c2f6351c84
font_01_sfnt_off000112e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012af7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF7 10740 bytes
SHA-256: e549a7e9442d6d6a429d4a940d5a08b6d681c430a784b5fb4ffe064a891af8be