Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf050a281a4f2e39…

MALICIOUS

PDF

95.2 KB Created: 2021-08-12 02:24:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2a013516a1f81a2be155338aa41d2b0f SHA-1: 7103f1ae97c13040d666e0faebac423319a1afef SHA-256: cf050a281a4f2e39ba10b75de8d8b82f6404c6e5868ab5a38f8b243621e272f4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting. These links likely serve as a link farm to redirect users to malicious content or download further malware. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://ketchas.ru/uplcv?utm_term=mapa+politico+de+puerto+rico+con+sus+pueblos+para+imprimir PDF link annotation
    • http://www.zaluziemalina.cz/userfiles/file/45263558997.pdfIn PDF document text
    • http://co-wemart.com/careeruserfiles/file/bivagumusukolori.pdfIn PDF document text
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/e4f901ec89d5c042599a0f5367660f48/1555847224.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/mogez.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093d2022668d---bidunijizurusogagogep.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/16090964ab77b2---38156851665.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160845f3028e6f---rarerumajebojakokaju.pdfIn PDF document text
    • http://bmsorganica.com/userfiles/file/busamisefodaze.pdfIn PDF document text
    • http://due.pt/js/ckfinder/userfiles/files/dutubifamopiperebefudulo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b21ba3a9225---36823211825.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/kokavatenir.pdfIn PDF document text
    • http://termocity.by/pics/files/88510943487.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/forifuruxuk.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/16075b6eab48c3---wuroki.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/qc4qmlemn0kea6l3ltt7mk8ck0/52221441226.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/fotesesufosogu.pdfIn PDF document text
    • http://tvtamminhphat.com/uploads/userfiles/file/46148966996.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/4urg5tdofjdqjki4cs6956ugn5/damimawisa.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/686a7fb985691e4965170e4033370305/mamajuwev.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/3491968665.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b0923e56ee0---56127544812.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/e9c7c94f5f9de89843dad9fc4edda83d/jemexipag.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160b5bc7c6c23d---dozunijeji.pdfIn PDF document text
    • 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_off00010a37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A37 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012249.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12249 19400 bytes
SHA-256: bb0386a3fe9075fe7a47349643af60fc72ffdff713181fe0efe5d0785dc6b383
font_02_sfnt_off00015486.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15486 10908 bytes
SHA-256: f9ce63aa6be736b37c563e830ea45081f34b930555abd63595d31318cd60af82