Malicious PDF — malware analysis report

Static analysis result for SHA-256 1087da872df3e210…

MALICIOUS

PDF

84.4 KB Created: 2021-06-29 12:51:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 3f25bf4c199e7d446c70cec29e24fbc0 SHA-1: dc6c7b4fc95f47a62e9983c73a421c38ea7f71ee SHA-256: 1087da872df3e21069c91d66d38e8b49a42a02167d94ad581cd158d704e97c04
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as a phishing trojan and flagged by an ML classifier. It contains numerous links pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users. The PDF structure itself does not contain readable content, but the presence of external links and the high detection scores strongly suggest malicious intent, likely to facilitate phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/gp4h0uri68hgicf2jvbucnsv8q/9768625086.pdf In PDF document text
    • http://thecobbfr.com/clients/4/43/4363d5a08aa72aedcf7f7d4dd0675897/File/17463509888.pdfIn PDF document text
    • http://murphysbeads.com/clients/54316/File/21042833841.pdfIn PDF document text
    • http://hasyo.net/files/file/wijibibirarewosir.pdfIn PDF document text
    • https://maspacientes.es/wp-content/plugins/super-forms/uploads/php/files/is0rma1l8r6f40jah5csh76h3i/39365449776.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/uae0ih61mn0c9pqob9jlg5a91o/79108182538.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/f30i6bvp1qi82tkhroefjdlo9l/15560589256.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/68890250766.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc88e1caed7---sutanipipipufigonimepog.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/fb538fe634e3ed704e7fbc388675c912/xazezezodepifijebu.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/d64tr0v1masuuj7cs6k63mbrmj/nikifoni.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ab858d40e93---busosisoled.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/vefigegolavijirofififivi.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/87350927652.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/frh1lrs9tk77cuc7sd398divqu/33525554541.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/zuzipazuvujizusasuj.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ecdd66631---67998183208.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608026d72ad4b---38916722624.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/doxekenur.pdfIn PDF document text
    • https://chupwo.com/editor_upload/file/serapagofofu.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8b687d3f9---52835545635.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=unlocking+your+hipsPDF 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_off0000e761.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE761 17256 bytes
SHA-256: 953ec9e5208616fcb99ef87d63979639592ef7a4d2c415248fa22c59a9c9c5b7
font_01_sfnt_off000114a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114A4 10576 bytes
SHA-256: 266b2d08e314cbec92c3933d75f422d3e026f2a2089e150be4ad92bc2f68a45a
font_02_sfnt_off00012ca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CA6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1