Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b3573fa7cbd31c…

MALICIOUS

PDF

256.5 KB Created: 2021-07-03 00:52:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: e77de69b29bc92940dd0724549565d5a SHA-1: 2270d154b19a4b6049b7b34d2d2737054558552a SHA-256: 77b3573fa7cbd31c8cbb0699091d3d5e830efacf20d60803b65d4d614af154db
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The embedded links, particularly the one pointing to 'daotaoyduoc.org', suggest a phishing attempt by directing users to a compromised WordPress upload site. Although no scripts were explicitly extracted, the nature of the embedded links and the ML classifier's output strongly indicate a malicious intent to deceive the user.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9753

Heuristics 5

  • 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.
  • 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://kythuatviet.vn/uploads/userfiles/file/vejizubozujuxosaxumole.pdf In PDF document text
    • http://reicar.dk/userfiles/file/14221234289.pdfIn PDF document text
    • http://gyobel.itpublic/file/4086693634.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160984c543183a---45758492894.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/gm2q5muenfua0av1d0kbt8d2od/fawotevubagi.pdfIn PDF document text
    • https://folklorebridge.eu/uploads/pictures/files/46640367602.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/gifax.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/e06651a2bbb65e66267957af556b9a80/betijekebew.pdfIn PDF document text
    • https://dm288.rs/slicice/file/44145905798.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/ffe680c2a1946ba3250310163a5e2ee9/dajurifadused.pdfIn PDF document text
    • http://rudolphi.nu/userfiles/file/gabugaj.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/jmbqovos79jnp6bva0uus7dg6j/6742445002.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/deditovazilorebimudifoko.pdfIn PDF document text
    • https://kvkumariajnkvv.org/singhania/downloads/file/wozadasubix.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bac99fdfa00---65765351355.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/26694301773.pdfIn PDF document text
    • http://beiks.info/public/file/baxozar.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/20f254c432528c91dfa056063d894b81/12100975024.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/npie8vcqsni72pi84fs2d32dm8/21466314496.pdfIn PDF document text
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/5240108d79ad834d99d944786b5a6f13/zimevidamufozofitu.pdfIn PDF document text
    • http://royalgoodviewresort.com/Uploads/file/kuloxekuwinilimadimoromum.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/3de90f80c6a41b00f86dd47a4af1e37a/80844625077.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/walubo.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/wevotosu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=homeopathic+medicine+dictionary+pdfPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000375ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x375BA 10776 bytes
SHA-256: 6dcedfdc5b6a2acb62f300f8ede4b31d5e64f9ffda51da47204995efb7d61f5f
font_01_sfnt_off00038e4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x38E4F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0003a661.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3A661 27512 bytes
SHA-256: a37b1d8a32cc0461a7546164e7e738855aa4b59337c229fd1dac12c802597e4c
font_03_sfnt_off0003eb22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3EB22 1700 bytes
SHA-256: 15171638d69c9281a983de8a04f8d213e5ed86d33053034f6aa0dd130c4010d8