Malicious PDF — malware analysis report

Static analysis result for SHA-256 e39d65f8a8054843…

MALICIOUS

PDF

75.3 KB Created: 2021-06-14 00:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 13f6dadb24ce6df4685719c46aae7e81 SHA-1: 712b314bb9e2b141df25a7d4b2baacec83b47f2d SHA-256: e39d65f8a80548439fb4027545b6b7d04baae26afa87abf3b064ddb3582ad063
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links to compromised WordPress sites, suggesting it's part of a link farm designed to distribute malware or facilitate phishing. The presence of external URIs and a 'download button' heuristic further supports this, indicating the document's purpose is to trick users into downloading a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://pixomot.ru/uplcv?utm_term=short+textbook+of+anaesthesia+ajay+yadav+5th+edition+pdf+free+download PDF link annotation
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b63b1233e90---nuramazekapefikivuwireso.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160892cf04a2f5---52769964424.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16085f15ede269---24931564332.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c11dd5638f3---xuponuso.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/63d9dbf0754bbda2904aafd55ef30358/75628276123.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/ff942edd635fe8d01ca1b757706bb38e/xiviwamekeruwadujulokeg.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb738a4b6c---26623928593.pdfIn PDF document text
    • https://teyadegitimvideo.com/calisma2/files/uploads/vidumudogalusilopozemesi.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/f531b18496464d57e300c201666fad6b/34720129225.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-5-14/20210514201445562042.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a296b41d446---31714722170.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/d4p9jcu3daesa9od8idj2vtj0p/37699675631.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/36520674748.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/6c3f4f15f9997b00703bf4a22b606f32/zuwexuzi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CA 5960 bytes
SHA-256: bcddf848eb96abdceb7e909a8b83e6aaaf606639b41d7c86cefcf97844845c86
font_01_sfnt_off0000fb2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB2B 10632 bytes
SHA-256: 489b9133bb1dac6579b9c836bee84b6c04200d961907d27864c6f129a1e968b7