Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2597e7293bcfea7…

MALICIOUS

PDF

75.6 KB Created: 2021-09-22 11:23:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6452fd65ffd8d027ae09749bd615139d SHA-1: 4d0d7a28e0b576aafd240404728b6135089d32a5 SHA-256: b2597e7293bcfea7ad90aad49c1046ed050ddd839bde331b2e3700b7f00c7e03
126 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous external URIs, including a link farm on disposable hosting, suggests a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, likely exploiting PDF vulnerabilities or social engineering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 https://laborke.ru/uplcv?utm_term=kuboom+mod+apk PDF link annotation
    • http://xsjsbzrw.com/uploads/files/lexoropituk.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/78959219282.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/fuzozep.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/2021921162565937.pdfIn PDF document text
    • http://nb-magnet.com/upload/files/98850756822.pdfIn PDF document text
    • https://asfus.net/virgsurv/userfiles/file/28490033492.pdfIn PDF document text
    • http://hoigolfbinhthuan.com/users/files/31833528103.pdfIn PDF document text
    • https://rybczewice.pl/userfiles/file/10091289698.pdfIn PDF document text
    • https://hongming-eco.com/userfiles/file/vejumevetunofomevezola.pdfIn PDF document text
    • http://soskuwait.com/outscapes/admin/ckeditor/uploads/ck/files/80386908452.pdfIn PDF document text
    • http://lisaarkin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/konusulokode.pdfIn PDF document text
    • https://gikguamerica.com/userfiles/file/letobobetolatur.pdfIn PDF document text
    • http://noithatachau.vn/webroot/img/files/zobamugirasusamanukexugep.pdfIn PDF document text
    • http://thetsaban3watnuea.com/UserFiles/file/93242608032.pdfIn PDF document text
    • https://nstyapi.com/resimler/files/6812760013.pdfIn PDF document text
    • http://calisnt.com/uploads/files/75324372130.pdfIn PDF document text
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/63697684418.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/778909fb909c7e240784d7dd56f38dee/xenap.pdfIn PDF document text
    • http://www.oomedia.com.tw/ckfinder/userfiles/files/numij.pdfIn PDF document text
    • https://suavitinhtannha.net/upload/files/lemirej.pdfIn PDF document text
    • http://trineckevzdelavani.cz/webpagebuilder/ckfinder/userfiles/files/bolulazolidaviwopi.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/vowukiwekili.pdfIn PDF document text
    • https://korzo-galeria.hu/files/file/zalazijoligedudodaxonokaz.pdfIn PDF document text
    • http://bio-scan.com/userfiles/file/mipud.pdfIn PDF document text
    • http://tzsunup.com/upload/wozotiwexipuxivepela.pdfIn PDF document text
    • https://akvaguru.hu/user/file/jijelogaziwolovojonopa.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_off0000c813.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC813 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e02a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE02A 10136 bytes
SHA-256: 86f8ad79519ae4a85f4ba951d9416101c91bd76223a202a0f730a426c152b5be
font_02_sfnt_off0000f68e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68E 16548 bytes
SHA-256: d01bc6e10a2158acbcd9140f609d4edb3bba97aae80e2c76f9f96634a335bd4b