Malicious PDF — malware analysis report

Static analysis result for SHA-256 4776a1e177ece17a…

MALICIOUS

PDF

80.9 KB Created: 2021-09-16 00:05:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 950c01523c670b50b8d389c36893e0e0 SHA-1: aec07a1fbd39709f90f3d4d4a539fe770fda65c7 SHA-256: 4776a1e177ece17afcecdf70e4c6b5eefb93ffa30ab7ade24fa22286c60b540b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm directing users to numerous URLs, several of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL targets suggest a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://tumsad.org/img/editor/image/file/naneti.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613263b64ca15---ramakotiretexisal.pdf
    • http://pekingtogo.com/uploads/files/44544244152.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/3d57158d3f62e9dee81c8e2f664dd2a3/73993792870.pdf
    • https://danielfelber.ch/userfiles/file/fipowulosa.pdf
    • http://contrast.no/ckfinder/userfiles/files/92223502141.pdf
    • http://nusamulticentralestari.com/Uploads/userfiles/files/92325001258.pdf
    • http://alpha-th.com/userfiles/file/83243154616.pdf
    • http://wabasnb.com/files/fckeditor/file/83165380761329176e5c7b.pdf
    • http://connectcontrol.net/files/userfiles/files/dowagevemamobunaruj.pdf
    • http://ipai-bg.eu/img/file/mekarobopokasebufa.pdf
    • https://nexusmediation.nl/files/91633647146.pdf
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161425f13420b7---genuxo.pdf
    • http://klhl.com/userfiles/file/tojekodikadubiserebewi.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161312f934f310---73344815244.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141442aaa72b---61254711518.pdf
    • http://perfectionistpaintingnj.com/ckfinder/userfiles/files/tuvebidimoxitemebo.pdf
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/mariwoweripozoxuwikege.pdf
    • https://veaodaibrahma.com/uploads/image/files/wukisilalojen.pdf
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/31945711145.pdf
    • https://taiwancy.com/app/webroot/userfiles/files/pakuwitotugupijukikuxa.pdf
    • http://inwallendorf.de/userfiles/file/93386078835.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=best+camera+play+store
    • 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_off0000d8af.bin
010c659844d9f132c464ee92b1cb90506407ab9a69bd64962af43159343bd3d9
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8AF 10508 bytes
font_01_sfnt_off0000f0b8.bin
4f6f5f41fc1ce42158160864f172b57002842ee71f359b7d62a825c959bc50b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B8 17640 bytes
font_02_sfnt_off00011e3e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E3E 16792 bytes