Malicious PDF — malware analysis report

Static analysis result for SHA-256 c403378c7edd1d7b…

MALICIOUS

PDF

80.4 KB Created: 2021-09-08 11:03:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e85f841ea7a2f159030a41482ba64ffa SHA-1: b30f26194c40b0e6147da07d3b1d777ff17dfd87 SHA-256: c403378c7edd1d7b4e3ec4bc5229914d5be91992ddf57e31da6de677f14f7506
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics, along with the ML_NYX_PDF_MALICIOUS and ClamAV detections, strongly indicates malicious intent. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure points to a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://drafthe.ru/uplcv?utm_term=jio+mobile+pdf+app+download
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/mf5oeplhiv9tniqd38bv847nah/98565501672.pdf
    • http://thumpamonpally.com/userfiles/file/82275289074.pdf
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/9fvc28h8g8s3caj5m017dvop32/16962824065.pdf
    • https://kaowei.tw/image/files/20210705_021549.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/lt4205uts40q44ufnuf3nbof01/37506633266.pdf
    • https://melz-feu.ru/upload/fexapatigovasanibibote.pdf
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b60d3fa67c8---32099217005.pdf
    • http://volareinmongolfiera.it/userfiles/files/37401539502.pdf
    • http://sziszolg.hu/editor_up/jikimi.pdf
    • http://fotofolliasanlazzaro.it/userfiles/files/rivarugelunaxaxopimupaken.pdf
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c2b4b1973b---12450484456.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be7359626c7---xixunasajarifibewufoxi.pdf
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/990d08d3e2a7d77a68e5bb6baffc7b45/89750662311.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082a1fca2466---forevowepegijewuba.pdf
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/9dc764eed18aef863199d3ffcfbb3ea2/balexiwa.pdf
    • http://barudan.hk/UploadFile/file/20210627122942330.pdf
    • https://bellcera.60km.com/upload/files/vofakozalanutuwi.pdf
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/ff47a48b3292ad6a677d12f1c48f7e0c/toxuk.pdf
    • https://mttrasportisrl.it/dati/upload/file/vironutanapixanaduvo.pdf
    • http://speaklifeiamgreatness.com/files/files/simimununosajan.pdf
    • http://thebankcardservices.com/uploads/files/kadufinijuvoraxinobejo.pdf
    • https://monographie.com/ckfinder/userfiles/files/59172306428.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610b7a8bdeac7---dubegodafez.pdf
    • 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_off0000dd17.bin
ca36959d59b82fdabf38f28995555f7578ea7e2042d399a5fe7ee2ba42f4d334
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD17 18040 bytes
font_01_sfnt_off00010b42.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B42 16792 bytes
font_02_sfnt_off00012359.bin
545506562f9bc51ca87ec6da527bacee5c78bdd1bccc40101826a87b889ef2df
pdf-font-stream PDF embedded font (sfnt) at offset 0x12359 10508 bytes