Malicious PDF — malware analysis report

Static analysis result for SHA-256 de544a51c9b1c2bd…

MALICIOUS

PDF

106.4 KB Created: 2021-07-18 13:17:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3ebef4392c893b842afd2424b3a7c085 SHA-1: ffc1a80a71d8e4faf954a5bcedd1c6695fc2e178 SHA-256: de544a51c9b1c2bd273fd96a50bfbb20e586572480555cf1c383b161a5fbc869
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised WordPress sites hosting other PDFs. The ML classifier and ClamAV also identified it as malicious, likely a phishing or malware distribution lure. Although no scripts were directly extracted, the nature of the link farm suggests it's part of a chain designed to deliver malicious content, potentially via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/30d4d8408379bc57f80863d3b009efbb/56042652214.pdf In PDF document text
    • http://gmkms.net/upfile_editor/2021/files/67626898500.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608701b4545e1---26446341816.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/7bde697c932b4814895cc8ed4de78969/torufodifaxopubi.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/3956cc5935f2c500bc23a3abf1d184c1/wugekonutupagajataminiz.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a32b25bbe22---fuvibeligab.pdfIn PDF document text
    • http://yds-wcv.jp/free_images/files/96793027000.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc28979377---53869019045.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160de6691f1cf7---tefadosi.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/fupalologeximewowelex.pdfIn PDF document text
    • http://poorclarescork.ie/images/xibufegudanumo.pdfIn PDF document text
    • https://bawaniint.com/ckfinder/userfiles/files/dozofikobitugawove.pdfIn PDF document text
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088cab71a3ec---wajovixasupukezagoko.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/16076a8b21c4f8---99788563934.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160893fbc94f07---lonuxekakepuxuni.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/negal.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/4e1a84c3fb8302ae05c112173a1c01ef/14714823598.pdfIn PDF document text
    • http://kochamsushi.pl/UserFiles/file/3334200964.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/1a884ac48d2d5ccf9b94e817d9a0b9bf/35086344987.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/7c76eff856a354ab88e0dc8cc5131cc1/18279178447.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/8219e9db7548e5acdaa788fad82bae27/69498974046.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/69172409974.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/172b59277069360534fbb834ce00ec2a/fasuzivexomusimeres.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160861fd6939df---wupib.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021050311490531.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=cme+solar+flare+todayPDF 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_off00013a31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00015243.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15243 19432 bytes
SHA-256: d0c746d67790a5f62685ef98ac760d9fae1f76e12c6f8ae9e5c92d3dcfd0491b
font_02_sfnt_off0001848e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1848E 10464 bytes
SHA-256: 658abfbb0d6c4ffa2c04c47ac61a0597e70fc1794592dbe78945403ec9c485ce