Malicious PDF — malware analysis report

Static analysis result for SHA-256 541a8b5b2734d01c…

MALICIOUS

PDF

71.8 KB Created: 2021-09-17 23:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: e8581a37215afb04ed36c57c23a96ec8 SHA-1: bf6494632a628ae3d83e352a71905baa3f662fed SHA-256: 541a8b5b2734d01c1e11e3c5a49174401fb554c5e7ae3c2329a5b46aa3a960a0
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic and the numerous unknown URLs suggest a link farm designed to redirect users to potentially harmful sites. The document body was unreadable, but the presence of many links points towards a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://hissekurban.com/resimler/files/1880215112.pdf In PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/50991252666.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/9d0388bb40cd0cbca9cddda699af9a4d/61694647991.pdfIn PDF document text
    • http://bubb.cn/up_file/file/nigerafamuta.pdfIn PDF document text
    • https://nasikampung.info/contents/files/fesavaduvawugivogumu.pdfIn PDF document text
    • http://sparkpro.lv/content/file/37705025107.pdfIn PDF document text
    • https://tarsiman.ee/files/file/9694758196.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/7738829950.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/86450413240.pdfIn PDF document text
    • https://basundharamart.com/userfiles/file/sadepebof.pdfIn PDF document text
    • https://moyaexpresss.com/ckfinder/userfiles/files/wetenuzilubipipoxirok.pdfIn PDF document text
    • https://qatarsecurityservices.com/public_html/userfiles/file/9576945384.pdfIn PDF document text
    • http://hp-cnc.de/uploads/files/44439795453.pdfIn PDF document text
    • http://fuhua.tumujike.com/assets/upload/files/202109130229468741.pdfIn PDF document text
    • http://vektor-bezpeki.com/userfiles/files/disakakirenabiruzipisima.pdfIn PDF document text
    • https://birutelorasin.com/contents/files/kulaporudutafirifaf.pdfIn PDF document text
    • http://clinicaveterinariaalbese.eu/userfiles/files/mapatal.pdfIn PDF document text
    • http://industra.sk/userfiles/file/mabovojufavixit.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/daxen.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/473923021.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/34338328753.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/61224334925.pdfIn PDF document text
    • http://uptindia.com/newsimages/file///varifudosa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=vias+terrestres+pdfPDF 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_off0000b4cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4CD 18152 bytes
SHA-256: 4111389c9df825b6366db52d78d38135e7657cd4fc644bee15bdd20d108580e7
font_01_sfnt_off0000e310.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE310 10192 bytes
SHA-256: 842feeb68c8b2f6e55dd3929fca088df5c757d57c0e0405266eab98ddba3c682
font_02_sfnt_off0000fa06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1