Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd5dc861d77d9b51…

MALICIOUS

PDF

77.4 KB Created: 2021-09-13 07:16:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 91b9d77a1916dd9ec98a47701892ac47 SHA-1: c1068496fc3994de27a6be698d88ad62e0935e1d SHA-256: bd5dc861d77d9b5112b243429329a014386d999eafdb55a41eb1c5aab808fc75
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are indicative of a link farm. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this is a malicious document designed to redirect users to potentially harmful sites. The ML classifier and ClamAV detection further support its malicious nature, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://zaintik.org/files/galeria/files/7655246263.pdf In PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16133f8e164a09---17608668662.pdfIn PDF document text
    • https://marljivo.hr/UserFiles/files/77753251048.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/9a377ae5b8ef09dc96f198b77266c5e3/3180699547.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/12557954055.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/329a76dd0372739a65496ea6bd87d62c/14290176509.pdfIn PDF document text
    • http://osmed.cz/app/webroot/files/files/bopatidomal.pdfIn PDF document text
    • https://abandassociates.com/ckfinder/userfiles/files/56922747524.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/zatadeba.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/48225665626.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/56312774938.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/92854938546.pdfIn PDF document text
    • https://nstoplana.rs/ckfinder/userfiles/files/7904687900.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/gipureba.pdfIn PDF document text
    • https://rent-1.es/ckfinder/userfiles/files/63657338660.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/691acqa0alrjemn592vmui9kq0/35926051345.pdfIn PDF document text
    • https://mmgrowersg.com/ckfinder/userfiles/files/12304479246.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/nelugesulopifozibo.pdfIn PDF document text
    • http://unewstoday.com/task/userimages/file/xokeperovajupitaroganuke.pdfIn PDF document text
    • https://chungangroup.com/uploads/files/202109062226153407.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/70313164244.pdfIn PDF document text
    • https://ienter.bg/files/24155875637.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/63582495789.pdfIn PDF document text
    • http://optometrystaprzemysl.pl/userfiles/file/69391971412.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=lg+webos+android+appsPDF 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_off0000c87f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC87F 18400 bytes
SHA-256: d22890f7ca040fd65bb7a7ad27072832506487b267fdfe3ff7893124415ef175
font_01_sfnt_off0000f862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF862 10604 bytes
SHA-256: 4f7a0d110c7a0a0e2f8fe6e0bbaf6f15e64e9f66a837eec9407c2822db870f52
font_02_sfnt_off00011055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11055 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1