Malicious PDF — malware analysis report

Static analysis result for SHA-256 99498e6ea9f90c4c…

MALICIOUS

PDF

79.8 KB Created: 2021-07-19 17:28:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 29ed1f50ee86d408f531b05940dfba79 SHA-1: d645c1f1ee7c3a563a36e5097a79540fc077dc95 SHA-256: 99498e6ea9f90c4c26e128685bd5a2eb7c16a01edae996fc92fb596cc543fde3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users. The PDF also functions as a link farm, pointing to multiple URLs hosted on compromised WordPress sites and disposable domains, suggesting an attempt to distribute malicious content or conduct phishing. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • 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 https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/c3534cedbc59462f874d5065c1ee8e4e/wuperu.pdf
    • http://musclecar-taps.com/js/upload/files/28115057236.pdf
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/86727638373.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8d071528f6---91429011546.pdf
    • http://goopenapp.com/uploads/files/87304368320.pdf
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/22262652226.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160915baa87385---vumepivoseze.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607d99f34c3bb---8214561668.pdf
    • http://take114.kr/FileData/ckfinder/files/20210706_831DD380286D32AE.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/d0a26022d375ca477d4ce742ad77fdcb/dipejibufiwevurapawaju.pdf
    • http://jrpst.pl/userfiles/file/nozuzamuferifegafobigoti.pdf
    • http://www.jindatunnel.com/up_files/file/nexaliwetutowofosujuwez.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/c818ee0eef54b05d7232bc64bfd62dba/62606856708.pdf
    • http://starsunited.at/upload/files/dulizanirelumibeduganut.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c11ce1a6e8d---64400645285.pdf
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/bf8a995ea66f1b2a1053318dc0134dc9/36938632805.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f51cd0e94d4---74010159092.pdf
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608392331d784---32301845376.pdf
    • http://technoauto.jp/js/upload/files/pikifusunijagabutemunewop.pdf
    • http://msiutilities.biz/documents/92589865919.pdf
    • http://orikon.net/Images_upload/files/22774156546.pdf
    • https://asset-books.com/userfiles/file/betukikinazifez.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/7tqfovgq6fihnaadlbgb4fp62i/87948610443.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=adjectives+to+describe+a+tree
    • 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_off0000d450.bin
f93e644badb886d232137f32ca41c495cade22669587879ff44cc7464eaa388c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD450 10528 bytes
font_01_sfnt_off0000ec6b.bin
84c73ea3f4e0ecf764f2365d8abb1c227ea7feac390652541202382619d19447
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC6B 17556 bytes
font_02_sfnt_off00011a03.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A03 16792 bytes