Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5713515908ffa87…

MALICIOUS

PDF

78.6 KB Created: 2021-06-12 10:17:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f645d38b398d88a837e0ec75c0bce0c9 SHA-1: 50c8a535e9d62b5caa67d796dde019cedb17fbf2 SHA-256: e5713515908ffa8728d30aff99138ca8a511fe7239fd1b2b31b01eb46bc986b2
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised websites and potentially disposable hosting, disguised as 'Toefl exam preparation books pdf'. The embedded URLs suggest an attempt to distribute further malware or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crewmak.ru/uplcv?utm_term=toefl+exam+preparation+books+pdf PDF link annotation
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16091d2f8cd83f---vilez.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/1c605dab2a6f2a81ec89c7c08adb781a/28348386329.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/69303132912.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b62c7e8d39a---86849192233.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/5om59egn5u15gqh07gaulek6b9/moterurate.pdfIn PDF document text
    • https://wagaskar.com/media/kipawafa.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2866e7f49---53836097165.pdfIn PDF document text
    • http://hzbmsj.net/images/upload/File/botitakekuzuter.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094bb84ded38---foxidisi.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a94e9f7d0b8---jatisowixi.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607de71eb8ae8---72356448509.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/ttku4hboed3e2vh1cg98368836/25688650360.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/wudinizapexutiravuxusi.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/41hmcp7enu7skl9tqh79d45j36/lozesazuvujafujavagevelo.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3acaf9a93f---suvavisigef.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/24796363905.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16076c48b2faa8---lizotiled.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160796e81dcf8e---55523312022.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/42116559c042be21574c74b1fdb240c8/jogutokapefimufiw.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_off0000f5cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5CB 5408 bytes
SHA-256: 86e7a98d321b804e7eefad09404022744994ef0b756a2b3e89ebdef831b0c155
font_01_sfnt_off00010815.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10815 10296 bytes
SHA-256: af9ef5b3f10e2b7ee7c69ca905e0762d8bbcef55ed230533f707247812a1f753