Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfda6b55580e8b0f…

MALICIOUS

PDF

88.3 KB Created: 2021-09-10 03:20:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6cec3873906ab0c4d1a06d2bc5aea77c SHA-1: d03e444972f3aedcbeacd174b7fa2aa7bd0f1cc3 SHA-256: cfda6b55580e8b0ffb66eb7fafa3474596a327e1578201a00c2927648d84b9c4
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised CMS upload directories, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristics and URLs point to a malicious PDF designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://studiocariola.com/userfiles/files/fakowanevavovoxevibaxuva.pdf
    • http://textingrights.com/userfiles/files/miwobemuri.pdf
    • http://ocvitlucky.com/vietkiendo/upload/file/24555621243.pdf
    • http://nuovojob.com/userfiles/files/26248034565.pdf
    • http://www.mezmat.ru/ckfinder/userfiles/files/girejazuwegevuzol.pdf
    • https://1877painters.com/FCKeditor/file/dosetopotapenexukurejew.pdf
    • https://lapakunited.com/contents/files/1252196262.pdf
    • http://markjfox.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/19814999267.pdf
    • http://skupka54.ru/upload/m/mivumeladuwowolibu.pdf
    • https://jamisonfurnace.ca/userfiles/files/95539606718.pdf
    • https://zbmbudomont.pl/userfiles/file/wojiviwiwonizepogimakozug.pdf
    • https://mitrasuksesku.com/userfiles/file/84686636302.pdf
    • http://frutapac.com/ckfinder/userfiles/files/85072854242.pdf
    • http://avanti-kuhni.ru/upload/files/88145864452.pdf
    • http://itfkarnataka.com/cvsprojects/SSK/Source/2.0.0/images/files/vukaxeluvomafuvemev.pdf
    • http://nage-z.com/ckfinder/userfiles/files/semuketumijuxa.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339aa248883---tulufusugekesis.pdf
    • http://svarovani-tig.cz/userfiles/file/tojuvatanu.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a316b7777a---xesometofaxupobufadoz.pdf
    • http://ccadl.com/files/20210904160419.pdf
    • http://i-tos.com/userData/board/file/3430502017.pdf
    • https://erdenetpost.mn/userfiles/files/jumapul.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/bc73159076254e17861b7b4a6bbb4d6c/bunodupimujinirusakol.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=free+instagram+followers+increase+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee8b.bin
5440596c83caefc6ac1f63d88b36a3dc3656aa73f6b1f4d3c587789753ebf2f7
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8B 10976 bytes
font_01_sfnt_off0001081c.bin
b7b8c64a47b88a8c028f73241aa1a8338f0d83834e088b80af8825e8d365fffe
pdf-font-stream PDF embedded font (sfnt) at offset 0x1081C 19664 bytes
font_02_sfnt_off00013bf2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF2 16792 bytes