Malicious PDF — malware analysis report

Static analysis result for SHA-256 7e8a52a13c25fe99…

MALICIOUS

PDF

90.9 KB Created: 2021-09-17 13:48:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 21cc27d5d5f298497c81bef2a4415b5a SHA-1: 25db16988212baa1ea0d0ca3d72f65786e28dda2 SHA-256: 7e8a52a13c25fe99a9efc1fcd068f779e79e997cea9f52ee21ad726ae1ca64b5
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised or disposable hosting, as indicated by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, but the structure itself is designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://huntic.ru/uplcv?utm_term=danganronpa+2+mikan+tsumiki PDF link annotation
    • http://fruitsad.pl/images/file/juzorezekadofajelejimama.pdfIn PDF document text
    • https://tfsroanoke.com/home/tfs/public_html/new/ckfinder/userfiles/files/sakizipemoguzusarajenin.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/5554404810.pdfIn PDF document text
    • http://datong-travel.tw/upload/ckeditor/files/20210911154231.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/5g2olutd37in2an3cdkbdg8v46/13457581257.pdfIn PDF document text
    • https://baongochoa.com/upload/file/nebavi.pdfIn PDF document text
    • https://latework.cz/soubory/5578594838.pdfIn PDF document text
    • http://sibaco.ru/ckfinder/userfiles/files/jefatepozozebuxufawoku.pdfIn PDF document text
    • https://stepweystudy.com/ckfinder/userfiles/files/nibuvigokowubujivugad.pdfIn PDF document text
    • https://partnyor.az/userfiles/file/vakenagujelupobubupedet.pdfIn PDF document text
    • http://geopraxis.it/userfiles/files/8480140482.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/mulawotepelepalowopimuz.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/keminolupovi.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/8ddjurssqcp1dc8gnvm6ndpapd/3464023414.pdfIn PDF document text
    • http://boldogelet.hu/media/11148421805.pdfIn PDF document text
    • https://funke.be/data/file/todupogomo.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2439a5f4edfc7e45f2d15c5df3a0f1e5/82172534040.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/nonaxapagaka.pdfIn PDF document text
    • https://greenboo.vn/uploads/files/fujunilipasa.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/mutezoje.pdfIn PDF document text
    • http://livestocktool.com/d/files/zuwumokefedunalokefepixo.pdfIn PDF document text
    • http://studio70.eu/userfiles/files/mekupu.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_off0000f6db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010ef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EF2 10732 bytes
SHA-256: a22e8147c0252d263492d313024be991eaffc6f7f696cf4192877a28ee6ebb16
font_02_sfnt_off000127ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127AB 21184 bytes
SHA-256: c6c8bb856e4a5141a706d2dd96fe675f1cdbd387119ce79f4f3c8ee969c6d611