Malicious PDF — malware analysis report

Static analysis result for SHA-256 7db9e9b45c272dc8…

MALICIOUS

PDF

76.3 KB Created: 2021-09-19 04:56:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 46ca4ef9eca9eb0ec9c991eb25f76a5f SHA-1: afd86bbbccfdee7a1cb5bab33c8d1e4baea8220f SHA-256: 7db9e9b45c272dc843bd60b62986cbb872550ba456969540141eb3204eb66bb0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs, suggesting it functions as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically points to this behavior, with many distinct hosts and a high number of links per host. The presence of embedded URLs further supports the attack pattern of directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 https://allytemp.ru/uplcv?utm_term=var%27s+vr+video+player PDF link annotation
    • https://bczenekar.hu/files/file/94733552603.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/juvuro.pdfIn PDF document text
    • http://tradotel-riviera.com/file/viritogozivodavetegiri.pdfIn PDF document text
    • http://vesimport.ru/userfiles/file/bebolobupiluwojez.pdfIn PDF document text
    • https://allianztc.ro/files/file/75009231854.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/10071561839.pdfIn PDF document text
    • https://noventa.cz/media/files/file/2868359005.pdfIn PDF document text
    • http://yilip.net/userData/board/file/55722663784.pdfIn PDF document text
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/lisogapolijasedixil.pdfIn PDF document text
    • http://tythb.cn/uploadfile/files/31991313101.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/sinasojelimizob.pdfIn PDF document text
    • https://yuktogel.com/contents/files/wuxuritisiwalaso.pdfIn PDF document text
    • http://decaiyun.com/upload/file/2109051517063565927dj06s8ukbhf.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/68f9c94f4c4f6d50f9d6d4146a2e47bc/rikasimu.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/wirenubuganogogor.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/161371a0d53095---wotavujik.pdfIn PDF document text
    • http://sensi-leszno.pl/userfiles/file/41199133354.pdfIn PDF document text
    • http://autowassenindex.nl/images/uploads/25046926774.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/nexexaxiw.pdfIn PDF document text
    • http://home-plast.ru/foto/files/xojurotukowigule.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/golesamujukedas.pdfIn PDF document text
    • https://rgcsmt.org/ckfinder/userfiles/files/82473637744.pdfIn PDF document text
    • https://etre-cheval.fr/Applications/MAMP/htdocs/etre%20cheval/news_pix/file/10748276012.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/48069237475.pdfIn PDF document text
    • http://regcureguide.com/files/files/temun.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/kabesufudaxefopakatupuzi.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_off0000c63a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC63A 10364 bytes
SHA-256: 090cd9941ce5e188dcd8f76c35575ac956aa0f11ed3974e50b0b7ede6d7b9468
font_01_sfnt_off0000ddc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC3 17540 bytes
SHA-256: fa81653af4371170c1c50539f183ae5c5aae0cb6bb47a27763f644db8b2f6355
font_02_sfnt_off00010b68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1