Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a4c57b9ce5fc783…

MALICIOUS

PDF

101.8 KB Created: 2021-07-03 00:43:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: c2b31caf23bcc7f4d82f2b22e89a7446 SHA-1: 8dfdd3a78a8229118094a490d8cce64a4f94de12 SHA-256: 1a4c57b9ce5fc7833a01523298dfee8e09d55d892a4b44ab5cfcd5907be21047
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to potentially compromised WordPress upload directories and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for SEO manipulation or to serve malicious content. Although no scripts were directly extracted, the PDF structure and URL patterns suggest it's designed to redirect users, potentially as part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9874

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://nnkcreations.com/userfiles/file/mitepijobovotalenivabane.pdf In PDF document text
    • http://maxbrio.kr/files/files/jurolovebexifovobegi.pdfIn PDF document text
    • https://banghenails.com/upload/file/zekovizitegajoninu.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160b69e31e44e8---goximixisew.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076ac8d42391---67696017418.pdfIn PDF document text
    • http://billsky.ee/files/file/23714907522.pdfIn PDF document text
    • http://hilimall.ae/uploads/files/gijisab.pdfIn PDF document text
    • http://alptw.com/images/files/99565527494.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/4mgkj8u8a8pr7rapdqn4e1kntt/88485512434.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/dda6326d146270a569ce236d6a0a7059/tulapajufodotufavedixixi.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/92616174952.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16099b93428fe4---79933237445.pdfIn PDF document text
    • http://ohappy.org/userData/board/file/12448400882.pdfIn PDF document text
    • http://seyrimerdin.com/userfiles/file/72509649697.pdfIn PDF document text
    • https://krono-original.vn/Images_upload/files/66722276191.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/79570515148.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7141a380de---garutozotigixanulaf.pdfIn PDF document text
    • http://aggengr.com/uploads/CMS/file/dikavasudufexojubudaw.pdfIn PDF document text
    • https://sonarmusic.hu/up_image/file/17904939071.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/9aa11daa73efa592a09f2df560ea86b0/74340195498.pdfIn PDF document text
    • https://alice-immo.com/userfiles/file/73497120871.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/2c1836ubdtrpeuflbrmf1cc57p/48344856538.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/suwipedokofemif.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160d07f74c537d---60202135480.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=the+tabernacle+diagramPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A2D 21044 bytes
SHA-256: b731c8f33c3655f3f3722fb82aef2d832649c6ed7c6b370413ef757f170e0d52
font_01_sfnt_off00013dde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DDE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000155f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155F5 10632 bytes
SHA-256: 62308476079af2594239483a6183022f6be1e94b3c7326e7802395bdd7068d23
font_03_sfnt_off00016dce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16DCE 17892 bytes
SHA-256: 33d2f4d04d15669e353b2ee61ee12f4e8ee1dcadb3fa94170f3c59b95017ab40