Malicious PDF — malware analysis report

Static analysis result for SHA-256 a406e3f237a8ee9c…

MALICIOUS

PDF

69.9 KB Created: 2021-09-08 02:13:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7cc0e7cde0840eb1f1024e8a2d931847 SHA-1: 83adf22761b985e662838ddad042d2dd45e76f01 SHA-256: a406e3f237a8ee9c50cb2d7e35b744be584ed746a4daa110bca0de4ed2b419a2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It functions as a link farm, containing numerous embedded URLs pointing to various domains, some of which appear to be hosted on compromised CMS platforms or disposable hosting. The primary purpose seems to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 https://assignmentmart.com/ckfinder/userfiles/files/36587231146.pdf In PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f58800550d---tamularatenoweb.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160d8303461abb---66594150492.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/97172753232.pdfIn PDF document text
    • https://anninhsieuthi.online/upload/files/38773644341.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/a6f311f01aee7978c451506e9c238285/22906325927.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/c544dfa41f955ff3ca4264613b637b92/82803384060.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/43296292814.pdfIn PDF document text
    • https://moolans.com/uploads/files/tavumaxasolovujo.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16071fd526fca4---37304501273.pdfIn PDF document text
    • https://nhathuydesign.com/wp-content/plugins/super-forms/uploads/php/files/faik04so8id2jvue76vt0p02th/sifusupizadiveroxurowisit.pdfIn PDF document text
    • https://universitecentrale.net/uploads/FCK_files/file/1846573627.pdfIn PDF document text
    • http://jncs.kr/page_data/file/20210901035700.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/jn9ibbk1ati5noa4fgr7ah228n/31953814318.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e16942ef7---32190173960.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/69b05c82fa080ad9a8c8ebbc54572bcd/3618955398.pdfIn PDF document text
    • https://fotokeramika.bg/userfiles/file/79280632359.pdfIn PDF document text
    • http://ux-school.ru/files/files/xitinufosekubadupabasi.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612cb09e756bb---27722480211.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/e38929479ee17cf1ab273cfa01e30c00/79775851958.pdfIn PDF document text
    • https://evergreencans.com/userfiles/file/xarurujebijuxagep.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160b472a584757---norunepifizuw.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/56428f2e30c721de1fb2213efe2d7bcc/rejikujinepawixuf.pdfIn PDF document text
    • https://telorgabus.com/contents//files/74342836256.pdfIn PDF document text
    • http://bloodfaces.de/attachment/file/zupimil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=die+casting+terminology+pdfPDF 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_off0000b38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB38F 14660 bytes
SHA-256: 63595fb1eeb3dfea56addfce3a3e6d78ff4f25b0d99aa7fc84bd1f7db3dff5e7
font_01_sfnt_off0000d833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD833 11076 bytes
SHA-256: 054cc41add3feb9110e21044dbe5f16f2d7bf2286eec0c2da38b00a1c484c489
font_02_sfnt_off0000f1dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1