Malicious PDF — malware analysis report

Static analysis result for SHA-256 b519d6fa49a13a67…

MALICIOUS

PDF

105.1 KB Created: 2021-06-21 17:08:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cc81241276b09c7a0c942687d09f319d SHA-1: 16651e634868aaeb7fc1c7aa4c6259f0a88926a5 SHA-256: b519d6fa49a13a67a9d52d2ba622aa88ed31dcf265d959b420d545743d8bccf9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many embedded URLs pointing to disposable or compromised hosting domains. These links are likely intended to redirect users to phishing sites or download further malicious content.

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://xn--bren-mgenwil-gcbf.ch/sites/default/files/fck-uploads/file/80545334436.pdf
    • http://lncxjzxxw.com/upload_fck/file/2021-5-22/20210522063354170997.pdf
    • https://china-glass-mosaic.com/userfiles/files/20210607_202924.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/8cc4080381f12535abee2f7ac78f3636/torebilujizeguzofalukali.pdf
    • http://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0e6f1b919---bafigesarefivuxuv.pdf
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/331204bf9b83f849b5abbfe72cf75c34/89076849402.pdf
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f004608da---tigik.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/e35f1f047bff6eb2a3e31ea6d0565a10/39936811789.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b75b1877c98---51721757294.pdf
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/thcigjuuaef85o1crnjfmbk7d0/vexabitenigisoki.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160a154d735424---59930564958.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607b798839baf---jirepoboweludotarukites.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/h019r9udf0hdn2gjdhav8kf247/podibebogasab.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a0635c46256---sugebof.pdf
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/a9580d2e323be86b651d014de9711eb0/50377883804.pdf
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/b8bbbd1ed3ef77e7128609665f6b3d99/rekimajugomamajegobujitiw.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=mozart+deh+vieni+non+tardar
    • 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://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015338.bin
5e6e4a73bee169553a6ea212e75d47e4b74d1e0c662b57e06cd51b4d8585d753
pdf-font-stream PDF embedded font (sfnt) at offset 0x15338 4608 bytes
font_01_sfnt_off000162de.bin
f59aa9b7de73043619ec9512ad08446df9b38c0b775b35b9a0ac1dd36ba295c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x162DE 12520 bytes
font_02_sfnt_off00018a2f.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x18A2F 4324 bytes