Malicious PDF — malware analysis report

Static analysis result for SHA-256 d41161b23ce4be30…

MALICIOUS

PDF

73.9 KB Created: 2021-09-03 19:05:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 57a684fbb41aa69cbd7eef34ae071ba3 SHA-1: 9eaf4757eed4aa0e33cd3732ba8349a6553d5d31 SHA-256: d41161b23ce4be3080767ac0bf5a21b1a3752feaa6bad974a1913a5f5872efc9
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to directing users to malicious content or further exploitation.

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 http://savvyais.com/userfiles/file/91450192278.pdf In PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/18621340680.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/xijegatiniwudewanenaworo.pdfIn PDF document text
    • http://skkl.cn/filespath/files/20210902055546.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a7bb6bc40---73985342007.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/1ec08ab13e1b13bc2f602b09163f630a/9839885865.pdfIn PDF document text
    • http://clingac.com/d/files/lenebogifu.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/wipomi.pdfIn PDF document text
    • http://kondicionery-elektrostal.ru/upload_picture/file/renulukatex.pdfIn PDF document text
    • http://nirmalamathachurch.org/cms_uploads/image/file/sugumimeboxapakutenuxama.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202107/file/1627020447.pdfIn PDF document text
    • http://namlongprojects.com/images/uploads/files/99500070241.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/97f7egg4vil1gm1eedha4e8tdo/47409535488.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/retokitugazaz.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/tumoruvuto.pdfIn PDF document text
    • http://keysrotary.com/clients/d/da/da683cbc30bfd632b0b364d14bdd38fd/File/28608892577.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/93768e002a9c986ae5e909fc4b8970d7/54647033730.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608d98f27ca71---kipadetujenawi.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/xufadifibab.pdfIn PDF document text
    • http://erdivigado.hu/userkepek/file/64261619538.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/25607506521.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=electronic+circuits+lab+manual+navas+pdfPDF 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_off0000b9e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9E1 17412 bytes
SHA-256: 35ac07658463711ee6f1ac43b7f178a68908c16c1aae9c835d008b0099c71e00
font_01_sfnt_off0000e623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE623 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3A 11072 bytes
SHA-256: 812e6e0b972b06f78bae42afd09a37f24126df6bd58eef897a450d2dfd1ab126