Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c711f97c5aa3b24…

MALICIOUS

PDF

70.2 KB Created: 2021-09-18 12:16:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: aa5a98fae152db5efff38015b2f5feed SHA-1: 6a20d7c1e927d17ab14d4b18c364d80ea6f508a2 SHA-256: 1c711f97c5aa3b240c6d89bff7517babfa30df109e7fe95344ec55dc0ef9e5f6
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous unknown URLs suggests an attempt to distribute phishing content or further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://sogelec-eng.com/files/ckfinder/files/8303923610.pdf In PDF document text
    • https://www.willmarshelter.com/ckfinder/userfiles/files/15134362591.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/43077824858.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/74037199408.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/87734955785.pdfIn PDF document text
    • https://felicitareonline.ro/ckfinder/userfiles/files/maronupunagidonitebakapi.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/sabasufet.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/57399009094.pdfIn PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/16736812210.pdfIn PDF document text
    • https://52fantasies.com/home/holly/public_html/ckfinder/userfiles/files/96119142048.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3970e6d18---sokuwiwixa.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/nv9qv85o6kce2cbh599jahoh3b/23177776770.pdfIn PDF document text
    • http://cmtoolsrental.com/user_img/files/72393530842.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/56555223466.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613838f3e05b2---63661969197.pdfIn PDF document text
    • https://brianhigbielaw.com/UserFiles/file/xosarobokanojorogeled.pdfIn PDF document text
    • http://poexali.org/static/image/_u/system/files/fefabar.pdfIn PDF document text
    • http://ivelinabozilova.com/userfiles/file/wedutalibunifasevovokel.pdfIn PDF document text
    • http://purplebyanki-com.bvirani.com/ckfinder/userfiles/files/radubafebakije.pdfIn PDF document text
    • https://pezenasenchantee.fr/userfiles/file/kazuvutigexatoba.pdfIn PDF document text
    • https://takipbizde.com/calisma2/files/uploads/bomuzavibafizekidu.pdfIn PDF document text
    • https://edusfera.pl/upload/file/138102139.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=two+types+of+graphsPDF 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_off0000b3c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBD8 10556 bytes
SHA-256: cf488a52d732f5cbacd331b808ad42e55535408b12fce215a8557c7272008679
font_02_sfnt_off0000e439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE439 15492 bytes
SHA-256: 9eace417c02ac8b57edbb6746e7680784ab8eb77b0c46134180b3ddd580e794f