Malicious PDF — malware analysis report

Static analysis result for SHA-256 113a141f93363a7b…

MALICIOUS

PDF

83.6 KB Created: 2021-06-27 05:27:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2d957b28f294eeccdcc734a8e91ae178 SHA-1: 25398ac9d204f9c16dfdee147cf66db73c5e5e07 SHA-256: 113a141f93363a7bd0744aaf3e2e169f8b9e47455d990690128dcbd3158a27ba
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It contains numerous embedded URLs pointing to external sites, many of which appear to be compromised WordPress uploads or disposable hosting, suggesting a link farm or phishing lure. The presence of these links and the overall structure indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://inwebjor.ru/uplcv?utm_term=class+6+english+supplementary+chapter+5+question+answer
    • https://bywuf.org/upload/editor/files/kerinobobuzojirodatutede.pdf
    • http://metabolit-plus.ru/files/file/43690812797.pdf
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/74350303221.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b467e14938d---zefigituroredixu.pdf
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/cbb6fe11fd7afd108db5c66ca26191d0/zosogasowegupu.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16090691c6667f---76060343747.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160cfe62621786---68815630197.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/1a049011268b741fd9a7c1c1fe5ac99e/61287859541.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb7bcd89a7---nisonelenidodumoziwanipaj.pdf
    • https://abe-rdc.com/userfiles/file/227845981.pdf
    • https://vivaldiroberto.com/img/files/mediafiles/file/48936903206.pdf
    • http://noithatnhapkhaugiasi.com/luutru/files/xoruregeva.pdf
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8d2008cd4---71009517352.pdf
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/da1e62cd2615eff94ad876af871d228b/60757183539.pdf
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16079b45a197c9---8278850036.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a6e8b14b6a4---suseravekuwa.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725857330df---zadarimes.pdf
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16087d9a6a03ac---vanulatatuzat.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/236tj422replvv4l8jre49647d/71226846054.pdf
    • http://handbook.hu/upload/page/file/1380581638.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160adb17a42dff---81141409147.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_off0000e17e.bin
5427b86a40bb94db676567803eca0b9ff61ed4a2d06ff822245d978289a52450
pdf-font-stream PDF embedded font (sfnt) at offset 0xE17E 11600 bytes
font_01_sfnt_off0000fcaa.bin
0e5cfb1e7209be4584ee8583ce901e3373b2634edd1d6aee3814d94f9d876fcc
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCAA 16972 bytes
font_02_sfnt_off000128c1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x128C1 16792 bytes