Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c4f7f96b92d935e…

MALICIOUS

PDF

74.9 KB Created: 2021-09-18 07:07:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a6ee5b21ba028f14f74de4dc67d4eb73 SHA-1: 8e4c2850490231aa5a5ca9a4d14902fe5a624a0c SHA-256: 4c4f7f96b92d935ec53bf7d8a65f714b6d61b4a992f62ab7c756c46b61f71152
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites hosting PDF files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates this is a link farm on disposable hosting, suggesting a tactic to manipulate search engine rankings or distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613215faeeaeb---59806008226.pdf In PDF document text
    • http://xindeshiye.com/uploadfile/file///2021090309270683.pdfIn PDF document text
    • http://inwama4.vn/webroot/img/files/ninixizafaba.pdfIn PDF document text
    • http://519pf.com/userfiles/files/kasujupitodajagufi.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/kejupejok.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/58917856019.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161395f61df4a3---venexulijiwijipiga.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161443a8fe066d---fugiwefanamup.pdfIn PDF document text
    • http://inruho.ru/ckfinder/userfiles/files/noxeworusijuwenov.pdfIn PDF document text
    • http://cybernet-ap.com/UserFiles/File/sapozoboxatirizufav.pdfIn PDF document text
    • http://www.huescalamagiaenfotos.com/userfiles/files/wemixakosefakejojudusira.pdfIn PDF document text
    • http://phutungvespaco.com/luutru/files/95780186874.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/63949667595.pdfIn PDF document text
    • http://www.oomedia.com.tw/ckfinder/userfiles/files/50715457858.pdfIn PDF document text
    • http://www.somdattabasu.com/fckimages/file/xawegozexe.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/96431991319.pdfIn PDF document text
    • http://elitsatodorova.com/uploadfiles/file/maxivud.pdfIn PDF document text
    • http://neteyes.eu/editor_up/96292800122.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/labukesozinofavatolenoku.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/39490336295.pdfIn PDF document text
    • https://granitabrasive.ro/editor_up/18026921272.pdfIn PDF document text
    • http://tichdiem.surecare.vn/uploads/userfiles/file/mutez.pdfIn PDF document text
    • http://boschvietnam.com/files/usersfiles/files/dagavimigusego.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/99832217721.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/6e2fd3fc70827c0351e3c9350f79b18d/mevemarutawusamavoxo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=dream+league+android+oyun+clubPDF 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_off0000ba80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA80 10800 bytes
SHA-256: d05f44bc2f28b45ba1825887d03003b7167dd9e2c40424eaa2c70b0a5025f7b6
font_01_sfnt_off0000d317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD317 19344 bytes
SHA-256: 8a789a4a3c11ec745ac927817340dd8ce6f0def67c512c424ad4acb793e32fb0
font_02_sfnt_off00010464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10464 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1