Malicious PDF — malware analysis report

Static analysis result for SHA-256 63b77615f4cf8ee4…

MALICIOUS

PDF

79.1 KB Created: 2021-09-06 18:36:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9597f0acc867950fdb57243069845dc6 SHA-1: fc6261127ea6880a325a4f8e920eff5f849301ba SHA-256: 63b77615f4cf8ee4e849af756914326db80ef33bb0d3b5c9d0e11f18e7fac540
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, detecting it as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to PDF files hosted on potentially compromised or disposable domains. The primary purpose appears to be SEO manipulation or directing users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://aaaexpressheating.com/userfiles/file/walavamalezofata.pdf In PDF document text
    • http://koryosushi.com/uploads/files/35170525611.pdfIn PDF document text
    • http://yoron.net/up/files/31080967041.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/74815084554.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/ef9094f9573acaf26ead8717f4cef722/dikolotusukunofod.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/85449895744.pdfIn PDF document text
    • https://weddingitaly.jp/images/file/44486329739.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/d40d2bd37f0adccde184964d03c24e74/gofiriwavojaro.pdfIn PDF document text
    • http://hkalc.com/userfiles/9149651666.pdfIn PDF document text
    • http://nature-revive.org/files/file/gojuxuserib.pdfIn PDF document text
    • http://magnumprint.ru/upload/files/gomejumenejitupuroge.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/negobagonunabubalaratu.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/17a61fd91f471c40d711a43f18d24e7b/bawuriwinaso.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a7889478348---83806168917.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/ponajex.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/wotuzijom.pdfIn PDF document text
    • http://zulassungsdienst4you.de/bilder/file/88718177153.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/49b3c4hneb2ju4g2sd18oikti4/dofetarenikigewevogi.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0586737f1---bokizalabuvodil.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/29522373802.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/e4rbcp4olork9rj6fkglbbbra3/mekifufapobuvekepa.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096849be1ac4---laxiva.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/8e4852b32baf6aa77d810f71f6eb3eb1/ludafis.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aacdc8bd89d---polusibupedoxoxij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=chapter+7+deviance+and+social+control+review+worksheet+answersPDF 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_off0000d1a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A8 16836 bytes
SHA-256: cc03f379569aca14e4bf9c8ebe8cb988b82e615d36087c71f993ad6b4b2f318e
font_01_sfnt_off0000fcca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCCA 10936 bytes
SHA-256: bb40c092b50c39a3870c6e7083d168df01082c5237d8468ac00aec9f096414ba
font_02_sfnt_off00011642.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11642 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1