Malicious PDF — malware analysis report

Static analysis result for SHA-256 6525216d3fb11f7c…

MALICIOUS

PDF

79.6 KB Created: 2021-09-11 01:09:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bf5f6aad29407c08603038e8b2bd15e9 SHA-1: c740152acd1134a94bd8a565b2e06443bbb238b4 SHA-256: 6525216d3fb11f7ce54bfefea83472ef42af713c389fb86f572c9a4249fc4f6c
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised WordPress sites. This pattern suggests an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://inwebjor.ru/uplcv?utm_term=vlc+apk+for+android+tv PDF link annotation
    • http://vilocom.net/webroot/img/files/binozok.pdfIn PDF document text
    • http://studioguatta.it/userfiles/files/62122667447.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/a4b6244cb923df922cbc69dac1e86cc5/tudode.pdfIn PDF document text
    • https://fajndoktor.cz/images/file/files/janenipas.pdfIn PDF document text
    • https://iuoshili.com/upload/users/files/77283127469.pdfIn PDF document text
    • http://champagne-marc-chauvet.com/images/files/mutadubemivogopegegerudu.pdfIn PDF document text
    • https://holycrosshealthcare.com/userfiles/files/44168794756.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/lemekeliveman.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/gegexutokozujuruzemo.pdfIn PDF document text
    • http://savytrading.com/userfiles/file/98005543053.pdfIn PDF document text
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/54361851837.pdfIn PDF document text
    • https://www.passion-rnd.com/upfile/files/2021/09/02/somumuwufonopirizepag.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/nugaratitegawuju.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/52b55c5cc9b55621b156cbd77f3f5a09/jewiwemonufilutolawama.pdfIn PDF document text
    • http://euro-ex.net/images/blog/file/rapenufidika.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/gapuw.pdfIn PDF document text
    • https://xosobacninh.vn/webroot/img/files/49245882142.pdfIn PDF document text
    • http://canoto.us/Images_upload/files/11300365344.pdfIn PDF document text
    • https://varbackaforskola.se/ckfinder/userfiles/files/xolelojejuxuwasew.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/13473847402.pdfIn PDF document text
    • https://marblobathware.ph/app/webroot/img/files/60142076061.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee2ec15cc7---45995957454.pdfIn PDF document text
    • http://hsi-international.com/ckfinder/userfiles/files/vilomilubudedozofuru.pdfIn 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://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_off0000d4a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ecb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB7 17176 bytes
SHA-256: b42d920b63deecd600bf233f5163cb3d4696491c8c7010af7aedb48e1bbc68a6
font_02_sfnt_off00011987.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11987 10440 bytes
SHA-256: 205e345e46e6e9a11050bcbbcfcda5843ca91d3ea5e35391929a559435c5be17