Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a3537bddec676c6…

MALICIOUS

PDF

81.8 KB Created: 2021-09-19 09:33:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f4aec52d9ca89512c008f5cc808a2e0c SHA-1: 2d06bf6df57180381d9147734bc96af4d53c5c00 SHA-256: 3a3537bddec676c6f29b5a37ce7523ec4740003fda830b4f09c0d9fff111647b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV, indicating it is likely a phishing or malware distribution lure. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting, suggesting an attempt to obscure the final malicious destination. The presence of 'utm_term' parameters in some URLs further supports a phishing or spamming campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://huntic.ru/uplcv?utm_term=telegram+app+for+web+series+download PDF link annotation
    • http://anhuizpyy.com/upload_fck/file/2021-9-9/20210909170246545441.pdfIn PDF document text
    • https://spacio.hk/attachment/file/gudekelufivezunigirafodi.pdfIn PDF document text
    • http://msmzizkov.cz/data/dokumenty/44978591782.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/20756711513.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614091149d3eb---45490989937.pdfIn PDF document text
    • http://hsound.ro/images/custom/file/lokefasogomafonaboxaxab.pdfIn PDF document text
    • https://ladangmimpi2.com/contents/files/83968909819.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f8caeec6af---44947358626.pdfIn PDF document text
    • https://digireg.com/upload/98575240386.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/susijemakafo.pdfIn PDF document text
    • http://paraleumarian.ro/app/webroot/files/userfiles/files/vilizuvijabanetet.pdfIn PDF document text
    • https://innovaciones-plasticas.com/imagenes_cont/sitio/documentos/jisisobix.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/megin.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613acb3274946---66299200571.pdfIn PDF document text
    • http://www.americaninvest.net/upls/files/rexasibuwe.pdfIn PDF document text
    • http://idrogastermoclima.it/Utentifile/FCKPage/file/33857598657.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/benenipowujuzerepesumidi.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/matexef.pdfIn PDF document text
    • http://tolaniprojects.com/userfiles/file/nudakofovolixidanajul.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/44819753811.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/36824114358.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_off0000dab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB8 10932 bytes
SHA-256: 573eb8e9252dc7c70384ba0e2f737924c4deee0691a3012bf0ee39fad758aba5
font_01_sfnt_off0000f39c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF39C 17976 bytes
SHA-256: 37b99301fb33d243ed40720ec0a750aea6bf9e9efb5651aa0c3bcd7d0af7ebf8
font_02_sfnt_off000121b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1