Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0cec611cb68cd82…

MALICIOUS

PDF

74.1 KB Created: 2021-09-30 15:44:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 9b8289173962b25e6f648fd88e43ace9 SHA-1: 48da9cb5a58767b6d765618c94e619e713f511e2 SHA-256: a0cec611cb68cd820f35e3137f67d858ef9ca9f7111c515e1336040185bc0136
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links to external PDF files, likely as a distribution mechanism. The embedded URLs point to domains that are likely part of this link farm, aiming to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://synerhu.ru/uplcv?utm_term=sensation+and+perception+goldstein+9th+edition+free+pdf PDF link annotation
    • http://logenamerica.com/userfiles/file/3443662366.pdfIn PDF document text
    • http://nousgarage.com/userfiles/file/subimusum.pdfIn PDF document text
    • http://apothepharma.com/upload/files/24610398507.pdfIn PDF document text
    • https://nikunjfoundation.org/ckfinder/userfiles/files/zapepefukukisiki.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/65550771147.pdfIn PDF document text
    • https://hoanghaie.com/Images_upload/files/48565270467.pdfIn PDF document text
    • https://4of100churchstreet.com/assets/media/files/82169041591.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/bezezodujoguradeku.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/61891982029.pdfIn PDF document text
    • http://bresky.cz/res/file/71329861736.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/zaduvarizerizofus.pdfIn PDF document text
    • http://acril.ru/ufiles/files/kefegi.pdfIn PDF document text
    • http://dc-42351dc5a6b3.prshots.es/uploads/userfiles/1630495075/files/tidolabolijoloxanaje.pdfIn PDF document text
    • http://csp.hu/editor_up/puminimib.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/c4f94a62bd2a190d1ad7729cc3f6b1d1/50053876259.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/bf12f2984aea5d732584fba04288f3f1/jixulelujezi.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/59910748328.pdfIn PDF document text
    • http://www.alliance-bio.com/user_data/editor/ckfinder/core/connector/php/upload/files/25338788203.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/jemozivi.pdfIn PDF document text
    • http://dae-young.kr/upload/fckeditor/file/57937676862.pdfIn PDF document text
    • http://www.likoda.com.tw/upload/ckimg/files/51079718131.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/fenosika.pdfIn PDF document text
    • http://gmtshipping.com/attachment/file/xewuvo.pdfIn PDF document text
    • http://findusafranchise.com/files/files/61811199364.pdfIn PDF document text
    • https://razredna-nastava.net/files/43666981651.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_off0000b981.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB981 18112 bytes
SHA-256: 3e7a4bcb10a569bfc7c6cb0006d9e50d0a6e9fe3c7bddcc6d138581b9d881723
font_01_sfnt_off0000e8a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000100ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BA 11140 bytes
SHA-256: f0862f2d0cbe0220077fed32d3c4dc74ac85fc7e29ad062b193a72acac8fbb16