Malicious PDF — malware analysis report

Static analysis result for SHA-256 73a4c1e3aa99fd1b…

MALICIOUS

PDF

87.7 KB Created: 2021-09-08 21:28:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 739bc67a94b3e39ab27f0a549abe791d SHA-1: 795fb5430473d6f770544fe95e8f7a15b5efff6a SHA-256: 73a4c1e3aa99fd1b24d5b262b0b976679eea3269b9ce8df336dae9e4db377e52
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a heuristic identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure suggests the PDF's primary function is to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://locktactyuma.com/userfiles/file/32400231688.pdf In PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/derolopexidokopelijoxitiw.pdfIn PDF document text
    • http://vectorma.ru/uploads/assets/file/rinawerukozivawi.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16133260abcaab---58806988926.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nipazip.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/zaputidoborodobamivuveb.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/24239265125.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/vizeloxogixumilulisop.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-1/20210901050815672553.pdfIn PDF document text
    • https://highendteen.com/userfiles/files/87848476549.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/tafugulugufubu.pdfIn PDF document text
    • http://harnettcountyhba.com/userfiles/file/riruxukuwegiwubamepomu.pdfIn PDF document text
    • http://redondoclassicburger.com/uploads/files/dedixizugekarotofufad.pdfIn PDF document text
    • http://menifee.hanasushichoice.com/uploads/files/68615565146.pdfIn PDF document text
    • http://kunbot.com/upload/files/lagepalare.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021090718202873499.pdfIn PDF document text
    • http://sql110.com/pic/fevejurudalajopamaluvabi.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/29189289016.pdfIn PDF document text
    • http://chinajessie.com/seadata/data/uploads/img/file/163098982691.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/tixemiteluniwawa.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/julonetomakotazigorurade.pdfIn PDF document text
    • https://www.kindspring.org/inc/ckfinder/userfiles/files/68139935982.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/nulokopizowefad.pdfIn PDF document text
    • http://baltyk.recykling-rejs.pl/imgturysta/files/gipobisisotuni.pdfIn PDF document text
    • http://wannawwannie.pl/userfiles/file/suwumuwegezitogeja.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=les+mots+de+l%27agronomie+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_off0000efe2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE2 18820 bytes
SHA-256: eb4193477e81e4b00b49745881d3f2c25ccd72093a6f67f427d3e8731a67c3d7
font_01_sfnt_off00011ecc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECC 10832 bytes
SHA-256: 3dc50fad1fa146add75d0513d46ccfdae6d5d0ae6b0700aa6d5dc522946c0535
font_02_sfnt_off00013794.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13794 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1