Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f1d37599cb5520b…

MALICIOUS

PDF

88.4 KB Created: 2021-07-03 00:17:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8723808ab05e68c2773f34524b0207db SHA-1: dc1c4012ad13d26c7b4c12131c8a48b494f764bc SHA-256: 9f1d37599cb5520bb9cd550b745719ee53f56ed43fa5c39a3ef5b7f3550c7498
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress uploads and other disposable hosting sites, likely to distribute malware or facilitate phishing. The presence of embedded URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://allytemp.ru/uplcv?utm_term=gameboy+advance+free+download
    • http://mvclassof1990.com/clients/8/8c/8ca0ba2c7a07c5cd1f21f9fc323c16c5/File/65941427331.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cab1b5cd94---batetopudixulololax.pdf
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c34a372009a---sisujofexamijulomig.pdf
    • http://geyikkimya.com/userfiles/upload/file/50372816471.pdf
    • https://myarchitect.es/ckfinder/userfiles/files/43169410419.pdf
    • https://xn--arbeitskndigungsrecht-best-5zc.de/userfiles/file/88959928620.pdf
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/e9381698330fc6fafce723f93afe4def/70863443863.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/d4549de82bd25b23a37575f9fdb10d03/wexudujutalalovagudugas.pdf
    • http://mtcclassof81.com/clients/0/0a/0a45bd3013a8cc77df817aa526a911b1/File/58551550065.pdf
    • http://aydinservis.com/ckfinder/userfiles/files/nijunerenumijuzixofifi.pdf
    • http://aaaexpressheating.com/userfiles/file/murutolukigowuzod.pdf
    • http://allmedicus.com/userfiles/file/webilij.pdf
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/1tkqmgmm7sa6bldkhse1ib6661/24732652737.pdf
    • https://anpheatingandac.com/nbloom/fckuploads/file/kakuzonaxalijirojep.pdf
    • https://ovistar-dz.com/ckfinder/userfiles/files/nuzenapivit.pdf
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/d5e65f2aeddb58b430976d944cceb40d/polinok.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/la4n4da3r9uhhj7av7bsdmu0m1/sesoxid.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16088671f6b06b---56912719605.pdf
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a348df0e2d7---30769072870.pdf
    • https://gbagencement.fr/uploads/file/92574000730.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6e49eb6071---rovabamibolelapakag.pdf
    • http://bhk-aindling.de/userfiles/files/39943106335.pdf
    • http://csc028.com/userfiles/file/20210701191231_7sbdiz.pdf
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/f012ebe5152b7330668dbf59a6624907/kateborejulekunukavena.pdf
    • 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_off0000f5db.bin
5cd1cbb05d1a269cb09ae1630ac9d3af5631414d5e5f6d4841821e5fb9481496
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DB 10724 bytes
font_01_sfnt_off00010e89.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E89 16792 bytes
font_02_sfnt_off0001269b.bin
e1d663f1b846200ddc65feb2aab5a5e066c82b7480364ba0e5d3ac48090c3997
pdf-font-stream PDF embedded font (sfnt) at offset 0x1269B 17364 bytes