Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5a84f0aaf5d4a5a…

MALICIOUS

PDF

69.2 KB Created: 2021-08-01 07:33:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 119d5e3c1d9b64752f401eeab3aa4232 SHA-1: 3248be17411e8c1bef9f734b0cc9c0e940a70008 SHA-256: a5a84f0aaf5d4a5a7bbaa6a388da4ebfeafe053aac720fc37ad1848d85e2a5ac
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to compromised WordPress upload directories and disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and does not provide clear instructions, but the overall structure and URL analysis point to a malicious link aggregation strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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 http://npxbyy.com/wang3_3_10_27/Upload/Upload/file/2021661146464363.pdf In PDF document text
    • https://akanaymatbaa.com/calisma2/files/uploads/21873789745.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160da2ddc29957---80159196975.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/sugaxasegakafimige.pdfIn PDF document text
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/lumaji.pdfIn PDF document text
    • http://cl-pub.com/files/files/79174726574.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c600263cbd4---95126302290.pdfIn PDF document text
    • https://prokoncept.hu/admin/blogfck/image/file/davekudepug.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202106/file/1622952485.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/afadedafb3dd7efa0f5feb8fd9d70806/38507062649.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16098c4b7b3056---bukezuk.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ea0f479a4---mimonepivebofazadiv.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/witefodewas.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d55734a606---26020831175.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/26d63d7722438ad30631359eea7f55d1/28962099421.pdfIn PDF document text
    • https://walnutcreekguide.com/wysiwygfiles/file/sazigafewarej.pdfIn PDF document text
    • http://sheeld.org/clients/d/d0/d021426cee8527c21a172be12ef3d645/File/94433743602.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/1cfc43060bdea830ffd18ae003129733/12167024612.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/fowoxuzolas.pdfIn PDF document text
    • https://fasaac.org/temp//files/limubolanaxibewufaj.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/wakub.pdfIn PDF document text
    • http://mastersequipments.com/ckfinder/userfiles/files/8150725308.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=voc%C3%AA+nasceu+rico+pdf+baixarPDF 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_off0000ae08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE08 15228 bytes
SHA-256: 707ab5cc743d6578fd40e800b0899e475533145d5b062f251daa99ad23b6f1dd
font_01_sfnt_off0000d4af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4AF 10940 bytes
SHA-256: 0c9e9bf7be9420709b0d928ac9bb135890b13aaa4f93b244b006c5256d2ed233
font_02_sfnt_off0000edb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1