Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfb9d0d28033ede5…

MALICIOUS

PDF

81.0 KB Created: 2021-06-19 13:15:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 20740355fa071b68a4980df60c28b21a SHA-1: 979443ace941d0159b59be064324cf30607838cf SHA-256: dfb9d0d28033ede53f063774d9e5991631b3f43ff7639d30c0d5e91cbac8ff30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains text related to a "Science olympiad circuit lab practice test", likely a lure to encourage clicks on the embedded links.

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://tractorpulling-emmeloord.nl/upload/file/fixuzifaruwibosulifade.pdf In PDF document text
    • http://bigsvatcharasith.com/userfiles/file/61721182407.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4aca77ceaf---36967744402.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc0dec391c---1649438917.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/602dd6b256b6617b98c1cacdf42067f4/tufovutuluxulab.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/fomifoxikuwawekevojifiw.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16085d82861f22---zukoxit.pdfIn PDF document text
    • https://lotteppta.com/beta/assets/file/xijifirixa.pdfIn PDF document text
    • http://stellarp.com/userfiles/files/79572963179.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/ifi8pplt1tfcs1c86jr7hhi85g/dijidujuno.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160721ce2e7a11---71494767684.pdfIn PDF document text
    • http://www.onlinetemsilci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f92aa2cfe6---24922293026.pdfIn PDF document text
    • https://blugarden.eu/file/84207513879.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b91eb2e2e33---37488865318.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c875b796c1---xafafuvu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=science+olympiad+circuit+lab+practice+testPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fddd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDD 5564 bytes
SHA-256: fca92f4016e0ba5761b26d4a0f47d5efebb3f1883ffa8970b11447538ce5e463
font_01_sfnt_off000110ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110AB 10736 bytes
SHA-256: 186b5e766c2181a9586c56aef540068e8861ebd53bba5918517f0886e1db1d18