Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5c5cf3f398acddc…

MALICIOUS

PDF

85.7 KB Created: 2021-09-24 11:51:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 181663788b2551b6865a730eca8064ae SHA-1: e24b6e4119aee27ecdb807feb52d4c4fbb13ea20 SHA-256: e5c5cf3f398acddc0bd50be9782a9e5dd1692891ad6eb3b714c9bb92e0c045d3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a PDF link farm, with multiple URLs pointing to compromised WordPress sites and disposable hosting. These links are likely intended to redirect users to phishing pages or download further malware, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://codemessaging.net/ckfinder/userfiles/files/66130070056.pdf In PDF document text
    • http://medicalproduct.hu/images/files/sazevigifulojotix.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb2878f4b1---31126268986.pdfIn PDF document text
    • https://amityhr.com/userfiles/file/74662093133.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///92952593114.pdfIn PDF document text
    • http://szyldkj.com/luodan/images/userfiles/file/12322583504.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613043ab80e90---76789077474.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/28537862010.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/45943811986.pdfIn PDF document text
    • https://galaxytraining.examinationonline.com/files/61659407466.pdfIn PDF document text
    • http://csc0535.com/userfiles/file/20210921204645_g4ozsu.pdfIn PDF document text
    • http://basumati.com/app/webroot/ckfinder/userfiles/files/92564458304.pdfIn PDF document text
    • https://www.sudicobank.com/ckfinder/userfiles/files/dodawarilafupuzeni.pdfIn PDF document text
    • http://bushurov.ru/images/files/51220320092.pdfIn PDF document text
    • http://dvif.fr/userfiles/file/90071524166.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16140cad3815b5---nakowagopoporiw.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/rezujawabasizepovevi.pdfIn PDF document text
    • http://openkomm.yussfone-crm.com/userfiles/file/binivipuxar.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137b0da3b902---8558265247.pdfIn PDF document text
    • http://vantaidongsaigon.com/uploads/files/zidurixatoxado.pdfIn PDF document text
    • https://nonbodepsg.com/uploads/files/lelajage.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=free+anime+watch+app+for+androidPDF 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_off0000ebbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBB 17344 bytes
SHA-256: 00530269dba1558160d2fe9b2d13b83a214791a2bb1ffab00364c2410dcbd2b3
font_01_sfnt_off00011890.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11890 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000130a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130A7 10732 bytes
SHA-256: aff34c2a2779fe38300175eea8a1ea72f2ee4a1685f3a2eb84d1add525f38175