Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d41af7b3677f196…

MALICIOUS

PDF

85.0 KB Created: 2021-08-29 15:56:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: e348b854d5fc4e90ea812743f7463dd0 SHA-1: 184bf808247c6beda559f383c7308cfdab929280 SHA-256: 4d41af7b3677f1961ae3ddb7a9129cf091ad635ace5c26dbeb6523e1683cec77
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a high number of links pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://yogo110.com/userfiles/file/11166308194.pdf In PDF document text
    • https://delcinfo.ru/img/files/files/42439291500.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec448bc007---58817065705.pdfIn PDF document text
    • http://aj-freight.com/ckfinder/userfiles/files/mojilozedusazazewis.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/rs4b1llq6kphlvcmhsp1ovseoo/48511556359.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ce5e4313200---85769859776.pdfIn PDF document text
    • https://avenue102.com/uploads/file/zejomidajufajotafage.pdfIn PDF document text
    • http://dakmet.pl/upload/78946757225.pdfIn PDF document text
    • http://skncn.com/u/files/lupugegage.pdfIn PDF document text
    • https://doucetplasticsurgery.com/ckfinder/userfiles/files/mitixoguzaz.pdfIn PDF document text
    • http://reclameindex.nl/images/uploads/7777353966.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160fd7f4c5e299---supozugevajunilovux.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/dotekem.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/7c43324g5besiam310rbhia312/66135276498.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608594cb9fa6e---nefunowoxobigakabefujubif.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160c4da961f8e5---10735890261.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/wiwotavewilenalabejip.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/28a30346f6fa6eb344f9d53f214ed1d7/45720274358.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/1kuo8tc56f72o3ls32lg88b07h/dalunozixakatijuzovowus.pdfIn PDF document text
    • https://kovosluzba-praha.cz/res/file/73594174206.pdfIn PDF document text
    • https://sieuthimaycafe.vn/uploads/file/paxunif.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c4f9d8eb890---kewegisozofaxa.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/pkgta2fv00ivu6nkuleqtdrp9p/pufoximi.pdfIn PDF document text
    • http://koovappadyscb.com/ckfinder/userfiles/files/delavuwifuzazavuxir.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/16711129765.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=suicidal+depression+meaningPDF 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_off0000e719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE719 10932 bytes
SHA-256: 56721911088bbc235e39d61ece4ec7838168fa890401391774c70d015223ee86
font_01_sfnt_off00010019.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10019 17716 bytes
SHA-256: eaf3949d850b3892bd7c3d3deec688c29c660b8ddc7e986ca85701a3fcc48aba
font_02_sfnt_off00012dd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1