Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f42134aa90e3292…

MALICIOUS

PDF

99.4 KB Created: 2021-10-08 15:42:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e30cf650c4b87ebed7652c4528e19735 SHA-1: 3bc294d2f485c74f925c510f2eaa919d168746ec SHA-256: 8f42134aa90e32929649572494c3053ad8231b107280714eb0d8db39bf1a51d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a phishing or trojan-like behavior. It functions as a link farm, distributing numerous URLs, some of which point to compromised WordPress installations. The presence of external URIs and link farm heuristics suggests an attempt to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=grey+bird+with+brown+head PDF link annotation
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b0abcc571f---vefaloleletafazoge.pdfIn PDF document text
    • https://www.seblocation.com/ckfinder/userfiles/files/54012942600.pdfIn PDF document text
    • http://autoscuolavalerio.it/userfiles/files/86891885948.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/gebaxatesurufasak.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/tosupilop.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16136c8b15ac8e---75628258870.pdfIn PDF document text
    • https://hitourkorea.com/FileData/ckfinder/files/20210903_6B3E86F10D1FFFC1.pdfIn PDF document text
    • https://alpinebadmintonacademy.com/ckfinder/userfiles/files/45735367514.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/439c0b1c1b787f336c519ab645b4d0f6/bofabirarapi.pdfIn PDF document text
    • http://boatmonies.com/uploads/files/jiwuzumaxeso.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/sovavekukixetapavasu.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/pewejopiborobumanig.pdfIn PDF document text
    • http://inciboya.com/resimler/site/files/daradomota.pdfIn PDF document text
    • https://aldwalia.com/userfiles/files/64405812034.pdfIn PDF document text
    • http://scuolascifondocortinadolomiti.it/userfiles/files/dafilajap.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/duwexusuzok.pdfIn PDF document text
    • http://tindangnhadat.vn/upload/files/tigofugikexaz.pdfIn PDF document text
    • http://ozsersogutma.com/upload/files/97013836687.pdfIn PDF document text
    • http://www.greenfield-sustainability.com/images/files/demokekopefoxijenewaraf.pdfIn PDF document text
    • https://kemxoithanhhang.vn/app/webroot/files/images/pages/files/rupuxenut.pdfIn PDF document text
    • http://evolution-dev.com/file_media/file_image/file/36878471423.pdfIn PDF document text
    • http://myhoteltrip.com/userfiles/file/71432790002.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_off00011b6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B6B 20572 bytes
SHA-256: c5e0f93c0eddacbcc5a7a75a6f23bd2ebfcaeead4763285b1ce8e2d562ce1252
font_01_sfnt_off00014fd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14FD5 10508 bytes
SHA-256: 3d269624f809ecdb155e600576ca299a33ea0abcc01f23cdd41b7597cc05d95b
font_02_sfnt_off000167c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x167C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1