Malicious PDF — malware analysis report

Static analysis result for SHA-256 40c50b02f558cea0…

MALICIOUS

PDF

91.4 KB Created: 2021-09-16 09:30:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: df8485239ee254120b8fec8232898fad SHA-1: 7ae2a889a30912f4fa35b96c2732914769c023bc SHA-256: 40c50b02f558cea093352bec42700c882ae281eda664fc122dc8dcc3aff64c7a
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various domains, many of which appear to be compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic findings confirm its function as a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://jerseyshorepirates.com/userfiles/files/gatunipolovuzuxe.pdf In PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16140f563168d8---82717213015.pdfIn PDF document text
    • http://www.americaninvest.net/upls/files/28955705824.pdfIn PDF document text
    • https://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/mobogemawojamolosuvo.pdfIn PDF document text
    • https://didaktika.drmix.cz/uploads/files/59150030425.pdfIn PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210909220756.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/89338454985.pdfIn PDF document text
    • http://tuderprogettazione.it/userfiles/files/40064406918.pdfIn PDF document text
    • http://melly-incendie.fr/img_db/53436314425.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/31544775552.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161367b53b4d66---noranujilavowigavitelixo.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613456beedb9f---pafakod.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/89073544887.pdfIn PDF document text
    • http://rotarycochinharbour.org/ci/userfiles/files/30276484874.pdfIn PDF document text
    • http://em-mould.com/ckfinder/userfiles/files/14353693565.pdfIn PDF document text
    • http://sxnqx.org/upload/file/Fl202109051328552592.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/805252016f39c6b1a1eef2fd63cc3292/5009510736.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/70160573465.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/wexiwom.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1614165999f752---80728180782.pdfIn PDF document text
    • https://beautydent.hu/editor_up/60055387581.pdfIn PDF document text
    • https://petala.gr/userfiles/file/banawevuvoguxatagox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=song+id+for+savage+lovePDF 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_off0000fc78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC78 19852 bytes
SHA-256: ff128e9e6583d941e84f75e465f167ff5d60d3a79c754d3a7db9742c4112be4b
font_01_sfnt_off00013072.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13072 10572 bytes
SHA-256: 461e15a7db0581f863ee865100e51ee532ba4cea43fb732cd9d0cb3acd2246d6
font_02_sfnt_off0001487c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1487C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1