Malicious PDF — malware analysis report

Static analysis result for SHA-256 844f23b12ccca367…

MALICIOUS

PDF

70.0 KB Created: 2021-09-26 12:54:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 464113ffcb028ea53ba44f3a1906ca62 SHA-1: 944a546b2ce6c4901f29a5990165bb517928730d SHA-256: 844f23b12ccca3672e1149061866a361247eb344bae45b36351521e4a51fe8df
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 WordPress sites and disposable hosting, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

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://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/628c11c43bb5e9b11275bf4b8b918d84/jofomalazipigizelewapul.pdf In PDF document text
    • http://jessie.vn/images/ckeditor/files/zibivukikegos.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/93311982765.pdfIn PDF document text
    • http://myphamhelios.vn/luutru/files/99025449502.pdfIn PDF document text
    • https://www.renfrewareahealthvillage.ca/ckfinder/userfiles/files/57191123701.pdfIn PDF document text
    • http://turismo-usa.com/files/others/tizoketivilenefuxalef.pdfIn PDF document text
    • http://www.ssc-ras.ru/ckfinder/userfiles/files/zumekupotojukivu.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/7009194875.pdfIn PDF document text
    • https://dienhoanghean.com/upload/ck/files/25275141063.pdfIn PDF document text
    • http://internet-trade.cz/UserFiles/file/87867898224.pdfIn PDF document text
    • http://www.colormotion.cz/UserFiles/file/96105215410.pdfIn PDF document text
    • http://mijinmotor.com/fckeditor/userfiles/file/nitavivakij.pdfIn PDF document text
    • http://tofuyatogo.com/uploads/files/85979032044.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/fotupep.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/jozoka.pdfIn PDF document text
    • http://azseal.net/uploads/userfiles/file/71066564231.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/dcbbd065ca09217da5a9fa47d73637a7/95797879957.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/nerelikutaratujati.pdfIn PDF document text
    • https://vasutaszeneiskola.hu/ckfinder/userfiles/files/23569395144.pdfIn PDF document text
    • http://brilsports.ro/userfiles/file///66952387437.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613fbff4ad1cc---saxutasowoduwefubibuguxu.pdfIn PDF document text
    • https://www.naabelectric.com/userfiles/files/72862391908.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/79755978409.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/33537918282.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/sezafotazojidarolinokor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=mortal+kombat+movie+2021+onlinePDF 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_off0000b3af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3AF 10688 bytes
SHA-256: 714707c0f70838d9750dd8742ee3ea53e1c918854a7e6a393b7297c56bc209b8
font_01_sfnt_off0000cc44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC44 15028 bytes
SHA-256: ea1d12d3988ece7327bdeb5ad288a02e0478b5d9c4662185677107ef57315ab8
font_02_sfnt_off0000f23f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1