Malicious PDF — malware analysis report

Static analysis result for SHA-256 4900670e05fda61f…

MALICIOUS

PDF

80.9 KB Created: 2021-09-17 02:53:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: fc689c54fdfcfc13ed1e1d0134bd9620 SHA-1: ee407401884782effcd89a7f4defd6ba09d4b2b3 SHA-256: 4900670e05fda61f4a0fee16859537382dd97ae3e0eaa2c960bab68b245da3e6
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating it likely exploits a vulnerability or contains malicious content. Heuristics indicate the PDF contains a link farm pointing to compromised websites and disposable hosting, suggesting a phishing or malware distribution lure. No scripts were extracted, but the presence of multiple embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect the user 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 https://whatproperty.ng/ckfinder/userfiles/files/79977371985.pdf In PDF document text
    • http://loaamtran.com/files/usersfiles/files/45213497613.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16131f5c5b83b1---sinowajufokiwidalujedum.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/zuzetixasalulir.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f0bc61229---94310629881.pdfIn PDF document text
    • https://pcparts.fr/ckfinder/userfiles/files/35752426938.pdfIn PDF document text
    • http://kondicionery-elektrostal.ru/upload_picture/file/46099882902.pdfIn PDF document text
    • http://uniquecharacters.com/upload/files/kokigemilema.pdfIn PDF document text
    • http://dpsnowodworze.pl/userfiles/file/38802360642.pdfIn PDF document text
    • http://cold.lt/userfiles/file/70225730908.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/leniderofeloloragetu.pdfIn PDF document text
    • https://longhoang.vn/upload/files/15066644911.pdfIn PDF document text
    • http://nhactheducthammy.com/upload/files/lisagadepez.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/789ffcf1a9c1667fe340e9e7d8dc0cb5/kelex.pdfIn PDF document text
    • http://albertf.madteam.net/ckfinder/userfiles/files/33226199186.pdfIn PDF document text
    • http://kleinschadenexperte.com/userfiles/file/88236799377.pdfIn PDF document text
    • https://vibingvibes.com/userfiles/files/78934196913.pdfIn PDF document text
    • http://art-ball.net/files/file/54608797908.pdfIn PDF document text
    • https://www.ocnistudio.cz/ckfinder/userfiles/files/fegowaxufe.pdfIn PDF document text
    • https://123natura.com/stockages/files/linatuvikituzo.pdfIn PDF document text
    • http://multiflex.ru/userfiles/file/43325643175.pdfIn PDF document text
    • https://hoangphatdanang.xetnghiemadndanang.com/uploads/image/files/24990438341.pdfIn PDF document text
    • http://jubileejec.com/userfiles/files/lulip.pdfIn PDF document text
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/tajiv.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/13487793774.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=king+root+net+5.0+0PDF 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_off0000d974.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD974 17528 bytes
SHA-256: aa5f8c044d290cddb449cfaa7da962a2e978d30eca8a067247ac3e33d516b8fd
font_01_sfnt_off000106d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D6 10220 bytes
SHA-256: 4e5fea1d0b50cb96c98e8989a11c648c88a5d6b7dbd017a3599d7f5c67b7b658
font_02_sfnt_off00011de6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1