Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e39cd95a5213df7…

MALICIOUS

PDF

88.8 KB Created: 2021-06-26 15:00:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 27d83c46bd6979c348ef15b23000b5cf SHA-1: 45f865eff2f3fb9c04c0f51c17517496a21b8392 SHA-256: 1e39cd95a5213df710603c03706edc806c825cd5e83a82cae7a190f9426e029c
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as a phishing trojan and flagged by an ML classifier. It contains numerous external links, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of multiple PDF link farm heuristics indicates a deliberate effort to obscure the final destination and potentially evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://queure.ru/uplcv?utm_term=coughing+up+thick+yellow+phlegm
    • https://genericdiabeticteststrips.com/userfiles/files/lufumibavisulaw.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/ed8ao6drd557io9kopqk3mh5i3/71734256988.pdf
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b568b4696---85036986431.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098b4c7b7aff---somupa.pdf
    • https://zoldlepes.hu/userfiles/file/33501648342.pdf
    • https://fentesmakina.com/paket/upload/files/jipojiwivezomez.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/eeea60904e907eb8ed1abd0918205876/53020140740.pdf
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b76e6de12da---niduvategubof.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16076bb8c0a65d---2927143789.pdf
    • http://libron.pl/fckupload/assets/file/25854083313.pdf
    • https://familienarbeit3plus.ch/userfiles/files/57358417161.pdf
    • http://rhodeislandalpha.com/clients/56223/File/kuratasufirobolowof.pdf
    • http://cbgnfinance.com/userfiles/file/jeduxemefof.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/826c6bbf8fabf0fcb0295bb5398811d5/12870161264.pdf
    • http://kapelski.pl/userfiles/file/97577686883.pdf
    • http://raiders71.com/clients/4/41/4134020f2f298c111575624a380fabfc/File/93433012609.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/j5ug83hl6fr80tgfkn3cmpvkj4/kefof.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608230121c3cc---dewumaperovameruvuzurobi.pdf
    • http://lbhodgereunion.com/clients/3/38/38e1f81cb1ac74d12d86c8ba87866b9f/File/lukakeditizanujex.pdf
    • http://files.ibiza-ferien.de/file/41052199404.pdf
    • http://fsgpj.com/upfolder/e/files/20210625132928.pdf
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607418c3c0e89---56806480916.pdf
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/fc842ffb0426acbd4839a82ac025693c/susutazatujefotawurupewa.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b875b9e2872---48117814210.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_off0000f949.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF949 16792 bytes
font_01_sfnt_off0001115b.bin
3ab81ae01510cd2f8986c7b20628033f1935124555ba5a97fc688754bb0ef49f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1115B 16876 bytes
font_02_sfnt_off00013d2f.bin
7129d07f4f41ebd3d24a7d477c8c99513a5a2c0e6cfa84c339afc214c4f2f7f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D2F 10816 bytes