Malicious PDF — malware analysis report

Static analysis result for SHA-256 4875630c21cf3ed3…

MALICIOUS

PDF

85.9 KB Created: 2021-08-31 07:23:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 63b9507982517d17ac234d46b8eef009 SHA-1: eec533eea5d52a5a249034b73c394beb7265336c SHA-256: 4875630c21cf3ed3e58b0a68abfa3e62647441abf22fe81f945cfa157a881315
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload storage locations and other disposable hosting sites. This suggests the PDF is used to distribute phishing content or further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://airflow-skateboards.com/upload/file/dudajidevisezobodoreputif.pdf In PDF document text
    • http://sweetbasketsbyjackie.com/clients/864293/File/buvidumapefabom.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f36f7c9cd8---44774136582.pdfIn PDF document text
    • https://ikuseikyokai.jp/ckmedia//files/tepevojovujekalipakedewi.pdfIn PDF document text
    • http://lamorenj.com/userfiles/file/loxomokevuzetusif.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/denakofotugobarug.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/562fa5sjjff2r6muomq8tshlcj/sovujixufemumejexegul.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f687dd21e8---kujokikex.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16075b3d383a9c---mofakigogowidororow.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/rusosi.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/b74aird0di778igppeeui9obr3/62905575797.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f7ef6bc8d---59285159521.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/40706dbb6c7fc1e2efb9f4930028af6e/zilesimibunozoforulotame.pdfIn PDF document text
    • http://35ct1.com/images/ckImageFiles/files/gakelutugabonimaruxax.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712dcf427a3---tudizafulodazekobape.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1609e6dd5b84b7---xoxovegoliguvase.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/99001438672.pdfIn PDF document text
    • http://shsuorui.com/uploadfiles/fckeditor/20210619/file/16240672375960.pdfIn PDF document text
    • http://vietsaovang.com/uploads/userfiles/file/99112134048.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/87802631803.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160babf44eb71b---gutaba.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/ui2n7shnjifql74l5i584ngc13/72293927781.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a778e039ff8---xunenataxefoketizon.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16124e79592f33---leluxasawoxavemorarig.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/kazivedilupekelekabi.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/34479384874.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=the+orchid+thief+authorPDF 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_off0000e9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E3 18424 bytes
SHA-256: 69df3aafbdd1a40f62cdafcf0b4b1780df9d42d27e50d87c680e5086ed24b6ed
font_01_sfnt_off000119d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131E9 10320 bytes
SHA-256: 57a3d1e2e65844f619f5671bcc68a785e162a0d34a462eeb2aa55ef3d9e0c4eb