Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c8c81ff5143968d…

MALICIOUS

PDF

70.1 KB Created: 2021-10-01 10:51:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0d92dfc38b8df1353d4665a7c9294fd9 SHA-1: 1f0115d53f51bd732a2c5c8e2962c72e008ed704 SHA-256: 0c8c81ff5143968df7f67a1cec35e08e4db43a95b6b88a6121cf5aa6746b62ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to PDF files hosted on compromised WordPress sites. The presence of external URIs and link farm characteristics suggests a phishing or credential harvesting attempt, or a lure to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://pistant.ru/uplcv?utm_term=change+video+thumbnail+android+gallery PDF link annotation
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614af5ff83c14---mifodojibopemavosikofewun.pdfIn PDF document text
    • http://cycling-software.com/files/file/pubavaporas.pdfIn PDF document text
    • https://tmtteks.com/files/14154867637.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/40182853540.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/49913547983.pdfIn PDF document text
    • https://www.almuhja.com/ckfinder/userfiles/files/48831514743.pdfIn PDF document text
    • http://majedalkarkhi.com/pics/file/91571527397.pdfIn PDF document text
    • https://ijmscr.com/ckfinder/userfiles/files/nimiluzefidifigi.pdfIn PDF document text
    • https://www.khaosanpools.org/ckfinder/userfiles/files/wonizaj.pdfIn PDF document text
    • https://lyna-garage.com/htdocs/cljr/data/files/10756570192.pdfIn PDF document text
    • http://quiltingacademy.info/fckeditor/userfiles/file/gorilir.pdfIn PDF document text
    • https://kheops-so.fr/ckfinder/userfiles/files/bupikimisafimujinegurefex.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/106fbcce677277c2d6bf2d53e3a6b7b9/bexexikufobanoparedub.pdfIn PDF document text
    • https://sgicorp.com/userfiles/files/milovamoliwidala.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/gusopuginokijodorara.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/cfa669442a3ffc89a0f9addf8063ce38/54954812909.pdfIn PDF document text
    • https://mudrun.com/home/mud/public_html/ckfinder/userfiles/files/rekigadepezerorolapezoka.pdfIn PDF document text
    • http://agierresrl.it/userfiles/files/dunuguwewajitez.pdfIn PDF document text
    • http://forumts.com/ckfinder/userfiles/files/11524744362.pdfIn PDF document text
    • http://onlinecommerce.bg/uploads/pages/files/39140931424.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/11331083685.pdfIn PDF document text
    • http://yigang-lin.com/uploads/files/202109160709079563.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/37324319031.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_off0000afa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFA8 16428 bytes
SHA-256: 41c6607de9e173969e30359b248347b01eab788f6ea930f4844069d4463d2a4a
font_01_sfnt_off0000d9d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F0 10976 bytes
SHA-256: 2764621427dbdee714ff94e31ded182fe6849b2186e0c989285e580bb2a060e7