Malicious PDF — malware analysis report

Static analysis result for SHA-256 a051dac518c3b6e1…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 20:36:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9b4ac719803b16d3b7538d0161f79c54 SHA-1: 3fbc14e92eade29443b2f570253ac3d36dacf0d6 SHA-256: a051dac518c3b6e1964d83bc2acc7d8fb07bebbeeaffc751fcd8c0d9e455ca55
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the nature of the embedded URLs and the PDF format itself often involves JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://uniroll.pl/user_images/file/40213278512.pdf In PDF document text
    • https://lodoshosting.com/calisma2/files/uploads/98837986025.pdfIn PDF document text
    • https://dubaimotorcycletours.dubaimotorhomerentals.com/uploaded_images/files/zabudakawujadaz.pdfIn PDF document text
    • https://ecotranslation.ca/upload/editor/file/taxanijixidijan.pdfIn PDF document text
    • http://archive-2014.humandoc.pl/attachments/file/winidovunisikujomimoxef.pdfIn PDF document text
    • https://guruvinodji.com/Userfiles/file/33212261614.pdfIn PDF document text
    • https://cncunse.com/d/files/51766440665.pdfIn PDF document text
    • http://jun-travel.com/userfiles/file/xererovojagoxasolavarize.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/16479102874.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/61865518568.pdfIn PDF document text
    • http://adbrf.com/files/fckeditor/file/2581150046145648fc9820.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/jevedi.pdfIn PDF document text
    • https://krainaogrodow.eu/zdjecia/fck/file/68505088445.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/lexobiwugefatokegeruf.pdfIn PDF document text
    • https://caror.hu/ckfinder/userfiles/files/29917470772.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614071d5b9c48---95210735437.pdfIn PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/zaxejumatisakarewojoxu.pdfIn PDF document text
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/84173330211.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/68035634822.pdfIn PDF document text
    • https://bipalisdemo.dashindonesia.com/userfiles/files/jipadobimunelexe.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142498328b57---39691672417.pdfIn PDF document text
    • http://snft.ro/media/file/sewavawelelubow.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/66261491998.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+cast+mi+tv+stickPDF 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_off0000d714.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD714 10244 bytes
SHA-256: fa0522b7d801c3458b6bb46976b8f6f50e0cf27a7d19346541a024f1882e36bc
font_01_sfnt_off0000ee29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001063b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1063B 17384 bytes
SHA-256: af9a870d4d1a0d93a1b988b2caddc5b1c1dbfd0bacba00f58470924a8f94ce1c