Malicious PDF — malware analysis report

Static analysis result for SHA-256 041b661563ffcd4e…

MALICIOUS

PDF

89.1 KB Created: 2021-07-07 02:41:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 94e984676b76ea5fca9664c734d1f5d7 SHA-1: c2dcf90883b3b3fdde2847bc31aee9cb66bd128b SHA-256: 041b661563ffcd4e6aa8d11f3f729fb8db20d8eb2d30919871887ef69fb654c5
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to compromised WordPress uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The PDF structure and embedded links are indicative of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609158455fcfa---mavolokozupig.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c733c2f138f---rikovik.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/7925072643.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/72018417405.pdfIn PDF document text
    • http://techbis.pl/files/file/68250311091.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/71043588230.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/sebutenuxa.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/voxakalid.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/86646143721.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/ritoruwuk.pdfIn PDF document text
    • http://autohondl.cz/userfiles/file/33729273174.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210706184728.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/cpuluapeta7cuibijmqr5niloh/71494947933.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/160c4cd711a5d3168c15423bfe7718f7/42001218576.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/83053000351.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9a9e1b1dbc---20293039657.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/8mi2ct86r6guh4o6b0es148527/gojowizutuxonipazoje.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078be2d43ec5---63473573268.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608507221f3bb---labisalonaxojozuva.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/cdfea43500d787a9de12befd4862c3d9/vudexonojib.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cadb271a36---2938104577.pdfIn PDF document text
    • http://goldenbaycruisesagent.com/userfiles/file/miraponedo.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/4828025879.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd060d3d09---59358773456.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/14994730270.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/55777688675.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=1943+two+shillingsPDF 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_off0000f724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF724 18392 bytes
SHA-256: 589bfc153c5a827498dd481a8dcb430f2a58c04dcb7f682dd2834fef0ce79bd3
font_01_sfnt_off00012762.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12762 10452 bytes
SHA-256: 6ab72966f5886a7dca359f9b62dbb80a66ad64ca5b06be8400820d91f7b99578
font_02_sfnt_off00013f29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1