Malicious PDF — malware analysis report

Static analysis result for SHA-256 37272388faeb5c86…

MALICIOUS

PDF

119.4 KB Created: 2021-09-01 09:26:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 53dbdc58e3f355129d2cc2e0fdab626f SHA-1: 8efe7d4d81e047b1636aeab19db814984bd0d394 SHA-256: 37272388faeb5c8663981bdeb82c422cbfe041e78a9a7b18666984b4cbe45ba1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to obscure the final malicious destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://sahodayabbsr.com/test/fckeditor/file/31415604003.pdf In PDF document text
    • https://bankkartya.hu/js/ckfinder/userfiles/files/42103492070.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/ka00d8ad7qjrgdondsaraun3r6/melunatukinuxekul.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611f7c2e65b7a---kugasevobafoteg.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609683afe5735---nawopenexufite.pdfIn PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/faterusud.pdfIn PDF document text
    • http://amouage-salon.ru/admin/ckfinder/userfiles/files/rokilivovez.pdfIn PDF document text
    • https://burgas-remonti.com/userfiles/file/rozepijujalunoli.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/2198175061.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160724146ccad5---12530666857.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/c4c1f3cf1d5126c3b3a22f9b37c7e597/26040178481.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612e75c327268---gelepevadopevufumuwuripo.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/6718435264.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16078143d8f98f---kagol.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607118e56f2bd---devefagenelesogeve.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609eb0e273b77---fesoveputasiku.pdfIn PDF document text
    • http://quadocdao.vn/uploads/files/dimerisu.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/65730278306.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/f031fdf527efd6d5ff7a00a83fa3f81b/64723868999.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/18037145515.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/kerijetama.pdfIn PDF document text
    • http://szalkasszorutacskok.hu/app/webroot/files/content/files/soride.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16099d8f9cacb7---1550000825.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/fuxajabigisevarani.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=gold+star+pulletsPDF 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_off00016f20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16F20 18872 bytes
SHA-256: 4b3157b9fbac5258326d4e673febdc2a1e0ce35512c891585bdb6f1396e50e47
font_01_sfnt_off0001a04d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A04D 10328 bytes
SHA-256: 7bce195bc0a8903a12a24264c1b9e511d0603e1b099bb24bf9212ac4732ef8a2
font_02_sfnt_off0001b7c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B7C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1