Malicious PDF — malware analysis report

Static analysis result for SHA-256 423ecc346e774ca3…

MALICIOUS

PDF

107.0 KB Created: 2021-07-07 13:13:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4882dad8570c47613918e5ecadf5835c SHA-1: 5cb6f5f7c1d753b1a57d5495d3ca8ad927a306fd SHA-256: 423ecc346e774ca313951d9fec997d73bd07c6e2a974a9b9fae2e24de391dadb
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and link farm heuristics point to a common technique for distributing secondary payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/vp24eostrql1m6ut88p5lr4ft1/xiworuzobibawukaf.pdf
    • https://tort-art.ru/userfiles/file/pukax.pdf
    • http://nguyenquangcomputer.com/upload/ck/files/26375807674.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/21q44v4vn37848n8d1j1qsrodr/zolevuninalozi.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/160816922334f9---xurerejipawudala.pdf
    • http://aihyang.com/userfiles/file/65380333024.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/4t8l61qe9gjl9gmgffjqf5odu3/wafavipozof.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d6d548093---fadojixopebeliboposa.pdf
    • https://guclupin.com/calisma2/files/uploads/fakikawibazeravev.pdf
    • http://qytbearing.com/upfile/file/mifikorotanixileloxutila.pdf
    • https://avgdesign.com/userfiles/file/56369593084.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/9or7lsnhk7c2b2g64f137qfjro/31870837823.pdf
    • https://audreyheselmans.com/_files/file/23242240966.pdf
    • https://ms02bet.com/contents//files/dowiwuritiwujaj.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d3a4c7726---rovub.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/7daf2a4be542b6042e8f784e1a1cc493/begijimagesuxitesixatexab.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/955dfc9508aa3056b48b536a124b436c/vexum.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16084fb4f5f4e5---78956770286.pdf
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a796cde3812---wabifawabo.pdf
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e183e176edf---13545511644.pdf
    • http://euredit-editions.com/userfiles/file/65433943714.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/32c2a5f61df9dbf5ded7fff2d2a868ac/kulaf.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=complaint+letter+to+police+station+in+marathi
    • 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_off00014482.bin
b03847da31bcb7a0c084fb8d7c5f32186c2405f1f1419b11859553cc2a9e26ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x14482 16280 bytes
font_01_sfnt_off00016e2b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16E2B 16792 bytes
font_02_sfnt_off00018642.bin
ad90bced052fb217f8490a60ac41444c7b16f75935394928de34145ac273bcc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x18642 10672 bytes