Malicious PDF — malware analysis report

Static analysis result for SHA-256 cde541abf71182e0…

MALICIOUS

PDF

88.6 KB Created: 2021-08-09 12:51:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b6de39b1f069e78f47f7ac2596f51b5f SHA-1: ffe13dec6e72225c2f82273bfb2234ea33ba3e40 SHA-256: cde541abf71182e04320cdc01bdb00a354d9ae5bc7c3cfb39afe5bd4bce8929f
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate this PDF is malicious. It functions as a link farm, with numerous URLs pointing to potentially compromised CMS uploads or disposable hosting, likely intended to redirect users to phishing or malware sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to distribute malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/8t0iejuaj16oc7fma7ca3cd6r2/vuwozi.pdf In PDF document text
    • https://atlastoursntravels.com/userfiles/file/34100972447.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2ec332d2b---zavapomupofosuwo.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c6826abeeb5---68369792264.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/89393524369.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/60221960415.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abc5a088c8a---saloxuzelezopefogaf.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/68417560500.pdfIn PDF document text
    • https://smartcirclegroup.com/userfiles/file/xatojetetik.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16071986ca348f---4844991430.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/7trje6vim82fdelcedjmrukrvm/bewepevapafadogovow.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/gmsfr8oip95sk70mp3ba1l6762/74609809386.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/bic868p2h7rlopu1rinstct7pm/98160840949.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/72782898095.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/25430524694.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/554125e7579fd6c9eec2285e39202b1a/vugolurisi.pdfIn PDF document text
    • https://ip-pharma.net/data/files/zujujezurinidobufuwemak.pdfIn PDF document text
    • http://cipetbhopal.com/webimg/files/37145719387.pdfIn PDF document text
    • http://gldbirdgel.com/user_img/files/32288570790.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/j8q3h827987qjn8e8u1gghogkn/jutamadovo.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16072a0ae3472f---58231239757.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/bosuwarikiduwoge.pdfIn PDF document text
    • http://myarrahnu.com/mo_images/files/vetutokofe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=les+pronoms+personnels+cod+et+coi+en+y+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_off0000f000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF000 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010812.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10812 19572 bytes
SHA-256: d5e118a20bc4b924e6aca6d4f402ad46091675dce2641edbd476270e63ea848b
font_02_sfnt_off00013923.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13923 10792 bytes
SHA-256: 42ef1a575de2348f0db846ed6d1e5b0a02c553075aee29b4fabe9ace8552b124