Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a8c2834afc716e4…

MALICIOUS

PDF

80.3 KB Created: 2021-06-09 19:18:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: aef33e443cea40bd15d18b4d8c2854f9 SHA-1: e3b7b97724c05556ed4a82d851ef53f370520bd3 SHA-256: 9a8c2834afc716e44a38872318c88e7bbbb10916e10ff803269429fad15ac001
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites, suggesting a link farm designed to distribute malware. The document body, though heavily obfuscated, contains text related to a "Brawl Stars hack mod apk 2021 download", indicating a lure for users seeking cheats or hacks. The presence of ClamAV detection and ML classification further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://wastran.ru/uplcv?utm_term=brawl+stars+hack+mod+apk+2021+download PDF link annotation
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2013d6211---tefawosuwikuwovasuwo.pdfIn PDF document text
    • http://www.victoriousintl.com/new/resource/files/25639797491.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021050312465373499.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c907f07f7698a0ee5cd6569934f2b006/wisasupipadaxuzokobux.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/eb74eb249e80111ce6cc83cb7c9b1f15/85240985307.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/50975911796.pdfIn PDF document text
    • https://www.lightingdynamics.com/wp-content/plugins/super-forms/uploads/php/files/504e774b3b6e245418f006a3084feb0c/45425375756.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16075f0ec4eae5---zudemadobovena.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b70c163f067---fabaferos.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608a48aed77d0---pepopewilosetixunufiza.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b10b89e4b06---44368491269.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a99d27e0f67---78022417949.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/54969611001.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096315fd7e16---98483509414.pdfIn PDF document text
    • https://securitegenerale.tn/userfiles/file/zonas.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/1e1977610c94480c417f3b83b16b3a79/52173304059.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eec2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEC2 5844 bytes
SHA-256: 476e373fac4e251de585c6376e94d008723cb6940d6ca178b22c8dc16faea9bd
font_01_sfnt_off00010291.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10291 21228 bytes
SHA-256: d376343d74f0b4837f78d627427c359124307b1d69922826ee94de456c077092