Malicious PDF — malware analysis report

Static analysis result for SHA-256 c76f5a0440f63283…

MALICIOUS

PDF

86.7 KB Created: 2021-09-20 21:23:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2da9ebfaa54c7bdfbe0c6d56f33cbe60 SHA-1: adff419658535e2d3df31acda2dfe6e1314b39a8 SHA-256: c76f5a0440f632832a8eff4f9b8ca2eb42bbdb4eb5f1fc045b5d439b8400c8d8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, embedding numerous URLs, with one identified as a disposable hosting link. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.veslovani-vsb.cz/soubory/file/zojora.pdf In PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/71280714593.pdfIn PDF document text
    • http://saxonrt.hu/img/userfiles/files/tazew.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/toginulebikagevep.pdfIn PDF document text
    • https://dongphuchuytai.com/upload/files/75425709225.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/27840543621.pdfIn PDF document text
    • http://malifer.hu/upload/file/73628401463.pdfIn PDF document text
    • http://friulanamarmi.it/images/file/mefodeletug.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/19894303357.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/161451315ec874---limidekelute.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/32367995861.pdfIn PDF document text
    • http://bytip.net/filespath/files/20210902142230.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/37443983146.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/nugopafogokujadifeporekiv.pdfIn PDF document text
    • https://contact-house.com/fckeditor/upload/file/lulibixegasogudipor.pdfIn PDF document text
    • http://kocavietnam.com/upload/files/wifix.pdfIn PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/20685404738.pdfIn PDF document text
    • https://sofupingame.net/calisma2/files/uploads/80134563970.pdfIn PDF document text
    • http://airzo.net/userData/board/file/zumemejidibenaso.pdfIn PDF document text
    • https://mkart.it/uploads/file/gidowenasarodolu.pdfIn PDF document text
    • http://myshopgroup.com/userfiles/files/43132568369.pdfIn PDF document text
    • https://autoskola-scp.com/files/razusisoruxawavefomin.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/xugolodilivufogeloto.pdfIn PDF document text
    • http://theponghop.com/upload/files/12436120829.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/xujesupetuwi.pdfIn PDF document text
    • https://goldfieldssanddrags.com.au/ckfinder/userfiles/files/ferip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=valorant+new+bundlePDF 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_off0000ecb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB8 10276 bytes
SHA-256: cbcd7c96ca2d46b4862705e908a257e2bd3f25c1d04bb48a5d00b8c03c80d0c6
font_01_sfnt_off00010401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10401 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C13 18796 bytes
SHA-256: 9ccdcf0811cab5b44c176d5ce4ebd53194a5623eee33451d04984428a4998602