Malicious PDF — malware analysis report

Static analysis result for SHA-256 5826c94a77f6aea7…

MALICIOUS

PDF

83.9 KB Created: 2021-09-05 03:35:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f758e2d696753f0575194e5c8192b372 SHA-1: 78b89bc2a32528fb7342c4531e56bd34ee12f415 SHA-256: 5826c94a77f6aea7b028611f263dbc8e8ca8f14fa839152ba460368087f61c93
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The document body is heavily obfuscated and does not provide clear textual lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aa11a77c067---47991760063.pdf In PDF document text
    • http://abwbaltimore.com/uploads/files/95362616303.pdfIn PDF document text
    • http://chsbicentennialclassof1976.com/clients/c/c2/c283bfa2537a82fb79a670aa087b4bd4/File/61807353907.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160825188c557c---75126078488.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/32bf0d1f8c3c635ac7eecde2286bbcae/25917126603.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/91518549236.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087e99c1fa31---mowemafutudefekerof.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/vilizo.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ffbae07c9e8---91553854038.pdfIn PDF document text
    • https://habibitours.com/ckfinder/userfiles/files/negumomuroxalidizulad.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/mupifoxakoj.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c9d27cc274---7394748399.pdfIn PDF document text
    • http://plantessentialoil.com/upload/files/15941132286.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/xafenire.pdfIn PDF document text
    • https://helicopterleasingservices.com/userfiles/files/67521541965.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/bd7e14ec5fa04428064c369ca3581841/14464045884.pdfIn PDF document text
    • https://mujeresenmovimientoplus.com/userfiles/file/50199636326.pdfIn PDF document text
    • http://sequirk.ie/userfiles/file/54852064991.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/83941310489.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/m0cc9lqh2roo5kpenubue5e430/newilozuribuvalizifuxojim.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1610e1a4e71595---bamowakozunozawila.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/75657374201.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160ae9021236aa---lirune.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/95d325f5185078398c82cd10d045550e/komefizavirenirumojifaw.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081da979f8f2---51074942517.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=rehabilitative+behavioral+health+services+provider+manualPDF 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_off0000e362.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE362 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB74 17048 bytes
SHA-256: 358d25b6a9e7bf4d5298bc9b5288cff965d5026657badb56e06629650d9dd5cb
font_02_sfnt_off00012795.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12795 11132 bytes
SHA-256: acc766f0f0ae9c91c9f48aa766ec0fb248fc28e1b8169d88c824475bc577170e