Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5edeb631951cda3…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 08:54:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dde448a7bbd513db2437ac384367e327 SHA-1: c9e5fff7ba2b2eb034477b91a33a16f491615134 SHA-256: b5edeb631951cda3cab98452603124be893c18ac8ed351c477c73cec9792102c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a link farm pointing to compromised WordPress upload storage, indicating an attempt to host and distribute malicious files. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded JavaScript is likely used to facilitate the download or execution of further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6604671ad---rotenenegugowonu.pdf
    • http://di-tech.kr/fckeditor/userfiles/file/sosogigazujudotom.pdf
    • http://abwva.com/uploads/files/27826379270.pdf
    • https://rarahil.org.np/ckfinder/userfiles/files/62465230282.pdf
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/jupevubapelexokolusa.pdf
    • http://corporatiegids.nl/uploads/files/94925919576.pdf
    • https://burlingame.com/wysiwygfiles/file/giguguma.pdf
    • https://htcpost.vn/vietpost.vn/img_content/file/desolidorum.pdf
    • https://www.corpeverest.com/ckfinder/userfiles/files/50852451767.pdf
    • https://afmiletisim.com/resimler/files/bubosijekinaz.pdf
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/44f9490abc975a36cbb8173b71c53100/92525491692.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161388ef6bdd6c---nugiwekuwar.pdf
    • https://kp-bs.ru/upload/files/21744766795.pdf
    • https://lotteppta.net/beta/assets/file/64310467939.pdf
    • http://rotarycochinharbour.org/ci/userfiles/files/xoniv.pdf
    • http://motolargo.pl/userfiles/file/52061844180.pdf
    • http://muacuoi.vn/Pictures/files/sunajubiteb.pdf
    • https://resulgame.com/calisma2/files/uploads/jobiniti.pdf
    • http://tw-echen.com/uploads/files/202109150407503787.pdf
    • http://ph-easycome.com/userfiles/file/46149302309.pdf
    • http://dongphat.net/upload/files/mekanekuveka.pdf
    • http://everestlodgelukla.com/userfiles/file/vibedaroxo.pdf
    • http://waycreon.net/bhaskar/yii/upload/files/nujopatukatubowum.pdf
    • https://hbfilm.ca/resimler/files/41635747167.pdf
    • http://runhouchem.com/upload/files/99495461615.pdf
    • http://sbairs.com/datas/files/9169552010.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=iphone+apk+download
    • 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_off0000d5ec.bin
be8148fa0cfa01bd7855d7cc52612ef70d0a7128b686c0a675d751ea94b3eca7
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EC 17564 bytes
font_01_sfnt_off000103bd.bin
859540b76d116f900863c77c383841b522db500d6f5c90f93dc4c31fabd35b69
pdf-font-stream PDF embedded font (sfnt) at offset 0x103BD 10160 bytes
font_02_sfnt_off00011a66.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A66 16792 bytes