Malicious PDF — malware analysis report

Static analysis result for SHA-256 6999768df28b54a1…

MALICIOUS

PDF

69.9 KB Created: 2021-10-01 13:54:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6bd7ef0d29a7f79a0c42c33f4b341b53 SHA-1: ec1077ac8561cfa834d009cecfa216b384adf4fa SHA-256: 6999768df28b54a1df279ddcf27948bd0892806a0ba68a3005962263efe25cb4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file containing embedded JavaScript, which is a common technique for exploiting vulnerabilities or delivering malicious content. Heuristics indicate it functions as a link farm, directing users to compromised websites or disposable hosting, likely for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=dls+2021+hack+version PDF link annotation
    • https://yantrasearch.com/ckfinder/userfiles/files/julenanowigagesikazo.pdfIn PDF document text
    • https://poldercuptrofee.nl/site/admin/ckfinder/userfilesfiles/4688123294.pdfIn PDF document text
    • https://lochoanggia.com/upload/files/65590094011.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/21379817759.pdfIn PDF document text
    • http://residenzaeden-albisola.com/userfiles/files/58113526579.pdfIn PDF document text
    • http://lecostationery.com/files/file/zisesomevivep.pdfIn PDF document text
    • http://avesta-hmora.boj.se/uploads/userfiles/files/mozonepe.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090623383552.pdfIn PDF document text
    • http://rts-3.ru/upload/files/45035803182.pdfIn PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/30446680603.pdfIn PDF document text
    • https://taiwan-tiaya.com/upload/tiaya_official/files/gazar.pdfIn PDF document text
    • http://mini-garden.ru/userfiles/file/rezerad.pdfIn PDF document text
    • https://yantrasearch.com/ckfinder/userfiles/files/gumusunasat.pdfIn PDF document text
    • https://hw-power.com/uploads/ckfiles/files/61481954753a9.pdfIn PDF document text
    • http://rosabaum.de/web/editor/files/rirodotol.pdfIn PDF document text
    • http://reklamaopole.pl/userfiles/file/38256138153.pdfIn PDF document text
    • http://mediasingrid.com/js/new/fckeditor/userfiles/file/46757217555.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614153c790471---nadalalirexobizobovuge.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/m2gltt4rn54dubbvjmbbu595oo/liseravaxiwabof.pdfIn PDF document text
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/74578213254.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1614d76a3105bb---25006248648.pdfIn PDF document text
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/72609043969.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/d767870480b182a4058e5a2ed5b75d2f/95794776751.pdfIn PDF document text
    • http://assotechne.eu/userfiles/files/sutoriz.pdfIn PDF document text
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/kaxazesogerivetik.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_off0000b429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB429 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC40 10684 bytes
SHA-256: b9c52c82c10a47d6c4d7fd8be9b31eed2f3c105fe9e38d6bd33220fbfbb5a093
font_02_sfnt_off0000e4cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4CB 14804 bytes
SHA-256: 0935d0d51081e4227875facb2517e75a28105bb8181102bb5c06b9649a5f00d6