Malicious PDF — malware analysis report

Static analysis result for SHA-256 e54d04e3c2bcf263…

MALICIOUS

PDF

83.7 KB Created: 2021-09-07 07:49:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4bfcc39fe12461240a80072da469a7cf SHA-1: 245f37d234bec1419b85d4a8266f5ab2ded40a4d SHA-256: e54d04e3c2bcf26395bd3720a6f7225870856142c63795ac5c614630d36be645
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the nature of the URLs and the PDF structure align with techniques used to lure users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • 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.
  • 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://smidgel.ru/uplcv?utm_term=duke+ellington+nutcracker+suite+pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/161010b875495c---pabexesuzebemibebep.pdf
    • https://zifu-tech.com/app/webroot/userfiles/files/fokurekurepamidozofele.pdf
    • http://medica-eg.com/userfiles/file/selutitesefinate.pdf
    • https://emprenderem.cl/files/191548791.pdf
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/4201escbvfp0gsemelfd1doqlp/xinamezoxijo.pdf
    • https://biocoils.com/img/file/kunare.pdf
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9fe7bcb4e---2095184666.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071110da9b3e---39812375273.pdf
    • http://phonphangschool.com/upload/files/wugawikal.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/e91a6ad614eb1d47f68c3bcb5d78bb7b/70249718442.pdf
    • http://ebiocell.com/uploadfile/file///2021062510354493.pdf
    • http://asckhn.com/acskhn/userfiles/file/78636972604.pdf
    • http://sisparts.pl/zdjecia/fck/file/22249695332.pdf
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/36dbdf4ad4761dad47907e2021bcdefc/56504058926.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/6oj1kaf5mraubemtfimscqjhm2/58717911414.pdf
    • https://kalyna.ua/sites/default/files/userfiles/file/15819670368.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/a21293cebd3af35ee9459a9d6f6da226/gevivezani.pdf
    • http://novehorizonty.sk/userfiles/file/zivunarezebogef.pdf
    • https://oncallanatomist.org/ckfinder/userfiles/files/71812998735.pdf
    • http://irinaburmistrova.ru/files/14925832410.pdf
    • http://littlepearlbooks.in/data/eimages/file/tufoxapubotup.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df85.bin
16387d5fad44ed9ae6606c1361f7c761deba64fcec1c9a17998799d8cc1b0483
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF85 10988 bytes
font_01_sfnt_off0000f8fd.bin
a094d570b6cffd3a5ed566a7c362111ba99464c9131ef197dfd287d5ed1ee17c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FD 18464 bytes
font_02_sfnt_off000128dd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x128DD 16792 bytes