Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4891d7790c35301…

MALICIOUS

PDF

80.6 KB Created: 2021-09-19 12:09:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f0d5e4dcbe26336ae2872d25be403a5e SHA-1: bb253feecbe06df73485bbe3f08b9c12aa9ab10d SHA-256: f4891d7790c3530186514e82bb2d7c5f5a6e209078370bf8abaa5466ca0ca96a
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 pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of a link farm suggests an attempt to obscure the ultimate destination and potentially host malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://cructi.ru/uplcv?utm_term=shadow+fighter+mod+apk+unlimited+money+and+gems PDF link annotation
    • http://kayapalinakliyat.com/file/xemiwirebuvuzipiwola.pdfIn PDF document text
    • https://ryokanclub.com/FileData/ckfinder/files/20210909_FA928360AE5C4F9D.pdfIn PDF document text
    • http://dges.in/userfiles/file/2457719882.pdfIn PDF document text
    • http://hebakotb.net/userfiles/file/18729703633.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/67134918405.pdfIn PDF document text
    • http://kd-council.com/upfile/files/mewasu.pdfIn PDF document text
    • https://www.khaosanpools.org/ckfinder/userfiles/files/mupuzuvivisev.pdfIn PDF document text
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/divtdjrdu6a397sm34u4ukucaf/66889163620.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210915155224225079.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/pusikabozizijibitu.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/jobofelum.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/kotivijukiwiji.pdfIn PDF document text
    • https://ngoctraithaibinhduong.com/uploads/news_file/terovurewaradobukoto.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/firim.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/jeropesoxiko.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/zonuworubetapetuk.pdfIn PDF document text
    • http://veszpremkosar.hu/_user/file/38799274283.pdfIn PDF document text
    • http://princeverma.in/uploads/files/nusorukowodebiz.pdfIn PDF document text
    • https://loonbedrijfschimmel.nl/userfiles/files/kezarumipinewumorekovuvun.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4648c2b6b---nokegifukamozasum.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/sufanidaguju.pdfIn PDF document text
    • http://kalikraft.com/images/file/48685655944.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139d94a0ba62---32653466479.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_off0000d4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DA 11412 bytes
SHA-256: 01ffe174206404abe4bc32bdc01a1274a70d36c09d54095a4782ea0ff73c7b01
font_01_sfnt_off0000ef77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF77 17204 bytes
SHA-256: 6d5bd19b4ba22e1bd848952f7e01960587192f94ce34fdbe4531a7fb465acdf1
font_02_sfnt_off00011c18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1