Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c8b770474dd5e18…

MALICIOUS

PDF

89.3 KB Created: 2021-09-01 20:52:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 1ca2f3cd6990b835c0a5a350d8ab2e96 SHA-1: 6c8c1636c4bb3d27e6881c4ea0050e23b27db9f0 SHA-256: 4c8b770474dd5e18c95a5ac7a2963495e30dfc5e57a7284cf02471ee54cfc4cd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9262951a2a---91541429984.pdf In PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c0a1010c9---biradafofisolitejimati.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c37f214e10---16620211257.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/vbrihmhiveindne321mluro10q/71056183377.pdfIn PDF document text
    • https://nhanloc.net/userfiles/file/74992551244.pdfIn PDF document text
    • http://cosyromania.com/media/file/51944678223.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/a71e77d3273dfc05f493e7f0369290ef/90360706556.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16085b00921318---lirir.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/49627864291.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/q9aiupangs4o121a7t5592biij/82891064224.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud//files/zikegatoga.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/92ca978990f5ef5f8e8259afe620caff/15172174459.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/3785d70da231f9f32ca9359090b14d37/fofemewovukidipaw.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c9d94e96eae---nopivowasuwuzakibemu.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/tenixi.pdfIn PDF document text
    • http://kurpinar.com/img/userfiles/files/kesune.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/ae1a153042ab0833fd0dc54d79efb8ed/jijutedanalagobu.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/nifufokovabi.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b6fda6a8e---75787713247.pdfIn PDF document text
    • http://ahdjcm.com/upload/files/vexuxikawafiborurer.pdfIn PDF document text
    • https://mai-avto.ru/upload_files/file/magopijalifusakusezili.pdfIn PDF document text
    • http://chapelguild.com/images/usr/mojowadizoredurejez.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/tolizomozirizaratod.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/73968514236.pdfIn PDF document text
    • http://mcutech.net/files/96334060955.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=all+creatures+great+and+small+tv+2020PDF 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_off0000f4a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A8 19068 bytes
SHA-256: 9f08cff7accbf85f5818901e246f2e0fa1721329ec3aa298022d75b59ed06a82
font_01_sfnt_off000125cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CB 10892 bytes
SHA-256: 16020e4640104ac3759b85b47a068df535245629c61735118bd6c3e808b7d18c
font_02_sfnt_off00013eef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1