Malicious PDF — malware analysis report

Static analysis result for SHA-256 436c72163ba422e6…

MALICIOUS

PDF

102.0 KB Created: 2021-09-04 20:23:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 730548bf48e36ed8b2a939e5ce5cca70 SHA-1: 8b6e9fb6c045da0fb2ecc319b2b880bf01969d78 SHA-256: 436c72163ba422e6e2124821bc7f8f4391910449ea03232bfc6c06db48d43d88
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to disposable hosting and appear to form a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these links. The presence of embedded JavaScript suggests it may be used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9877

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://kueapem.com/contents//files/rawasilubakozosidizolet.pdf In PDF document text
    • https://skyzoan.com/cake/beta/userfiles/file/jepazodenefi.pdfIn PDF document text
    • http://dienmaythanglong.org/uploads/files/47483992791.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/42db5ea2fb93837a2b5585a4a82b6567/fuzilelarowozat.pdfIn PDF document text
    • https://afayl.com/userfiles/file/bivuteburulub.pdfIn PDF document text
    • http://bioterapiazabiegi.pl/obrazy/file/sujegadojeref.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/2f1b0cf07be91c1d483af5f0ee38c659/69820159950.pdfIn PDF document text
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jadijoz.pdfIn PDF document text
    • http://gillsandgeckos.com/userfiles/file/47886454473.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/hdrqg3l1sf6c44k3l34rck8ad5/nodemujulipopunavese.pdfIn PDF document text
    • http://iphysiology.ru/upload/86914735775.pdfIn PDF document text
    • http://auapp.ch/userfiles/files/totatatumituked.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/90298588001.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/9703d50c465cd39a131de5b8772cd299/gatudovobadobigas.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16075aa80150ba---58361775316.pdfIn PDF document text
    • https://etonbio.com/newsLetters/images/file/zanejitixome.pdfIn PDF document text
    • http://chrislahoda.ca/userfiles/file/49685880640.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e122727e743---57864626258.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ada3ca2967b---26518019096.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/25008739458.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/cddca028eb820a21e4c84c9fb572bd6a/basatagesod.pdfIn PDF document text
    • http://gok-maciejowice.pl/js/ckfinder/userfiles/files/43897418600.pdfIn PDF document text
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607975d4ebe09---34741301111.pdfIn PDF document text
    • http://nutricion-intravenosa.com/wp-content/plugins/super-forms/uploads/php/files/d3d37640f52b6ce38fa95c76d4d3c67e/redeginusam.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/35293817792.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/43bcee0ebcd495a1193fc4135756149b/pozagilarim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=2013+subaru+outback+shop+manualPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012753.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12753 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00013f65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F65 18336 bytes
SHA-256: ec2047c39a0300ab7db2eb6b4e4f5a337fdfca598bfafe423c6b9718fb325b8b
font_02_sfnt_off00016ee0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16EE0 11116 bytes
SHA-256: b79a043f659d93f738e1c106dda56bce74b6db897afc3ae922597a955443c4d0