Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef4a3837aab24f65…

MALICIOUS

PDF

78.8 KB Created: 2021-05-30 21:09:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 64f459d44ca22ef17ed3a1dfbf8a23be SHA-1: 0deec12f69aafda12ed5c5105b9cc6a5d5c5db0a SHA-256: ef4a3837aab24f659784c6cfb08d5cc6a771627662177347e70823473e4caef0
156 Risk Score

Malware Insights

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

This PDF document was flagged by ML classifiers and ClamAV as malicious. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to a webquest answer key, a common tactic for phishing or malware distribution.

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 http://au-coeur-du-temps.com/userfiles/file/mubatizuli.pdf In PDF document text
    • http://amon-syotengai.com/userfiles/file/fedejunisa.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/f9bfa2fd0d1ccd54cfe00d0768381264/makigafevunosefuman.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a79ff0491---78840359276.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a69fef59685---lemirakesu.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/d20188b3a58f636fe87f0b488c59522a/sutubujupafenomonuv.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-4-30/20210430125149803064.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/021f2b1929f7b2713fa88e7a3b3daac1/fewakomebuvod.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0eb42307e---32075815537.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/betelurosezamobosad.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e900bcf76---5554611672.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/h193rivllp052tuut4dcac8icl/bopufiwiparexo.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1608d248153e02---wupapukibaf.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/9b721d07408e70af529703f6fcbebc93/rebafepewinuki.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/fomutomaludig.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/79d8jmr6gveo3afoctcl427fk7/1755004771.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/noletemizifikurakajoxel.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=atmosphere+and+hydrosphere%252Fwater+cycle+webquest+answer+keyPDF link annotation
    • 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_off0000f607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF607 5860 bytes
SHA-256: 265c23babab9366e23f80e27f393b9c92236af298ca06eaa2fb6b156a269ad64
font_01_sfnt_off000109e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109E7 10508 bytes
SHA-256: 22cd560f25b45e3fbed62b529192153683cb958730b847b411140e2d19d41729