Malicious PDF — malware analysis report

Static analysis result for SHA-256 c121ed8f51ccaf8b…

MALICIOUS

PDF

84.6 KB Created: 2021-09-20 07:54:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b91e204dde58c8c3430e4acf5204d90a SHA-1: 0638948107fa9ca8ec5835151dd82416913f2de8 SHA-256: c121ed8f51ccaf8bb0a637043ba2c2a3c6ee211bb17e7386e3c31adf840da97f
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised websites or link farms. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics suggests the document is part of a campaign to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6473

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=naruto+ultimate+ninja+storm+2+android
    • http://skrabl.pl/www/rpbd/fck/file/71758457792.pdf
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/21377243157.pdf
    • http://greensquares.in/userfiles/file///36507368399.pdf
    • http://jljemc.com/upload/files/13345959519.pdf
    • https://reclamesticker.nl/images/uploads/file/
    • https://derya.afmiletisimajansi.info/resimler/files/73245713806.pdf
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/ffa7b0c5bf8886f64b2c84e6ecd07d69/rodupafup.pdf
    • http://veterky.ru/ckfinder/userfiles/files/tuxiwugipa.pdf
    • http://timebymtm.com/upload/files/38275117765.pdf
    • http://esistore.lu/userfiles/file/bezajawibexufub.pdf
    • https://grandhotelbulgaria.com/userfiles/file/fisosewamewaviziram.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161395cc47616a---25051286403.pdf
    • http://roosprommenschenckelfoundation.nl/userfiles/file/85173120891.pdf
    • https://academiapreprod.riportico.com/userfiles/files/51035713129.pdf
    • http://woykoff.hu/upload/file/29792309812.pdf
    • https://wsbtitan.com/images/file/nunakapugogubofeza.pdf
    • https://galerie-louise.be/userfiles/files/zobiziloduzifesukifol.pdf
    • http://formel1vermietung.de/userfiles/file/11231715093.pdf
    • https://reparation-mobile.net/userfiles/file/jidelus.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138faf5243b0---fasutonax.pdf
    • http://haihengpharm.com/upload/files/76445845658.pdf
    • http://kme-kme.cz/files/file/74090100810.pdf
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/a783c1acebaaf2b8edd673228fd7b81a/57655533270.pdf
    • http://cardealer-space.com/js/upload/files/28293010697.pdf
    • http://www.pranabkumar.com/fckimages/file/61097239796.pdf
    • 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_off0000ec4f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4F 16792 bytes
font_01_sfnt_off00010461.bin
cd74bf0da683b8bcaa27a0e98c767a9b01148ec6d2821212e5bfd131cdd27444
pdf-font-stream PDF embedded font (sfnt) at offset 0x10461 18476 bytes
font_02_sfnt_off000134b5.bin
ee6590b32d2ae41bfbccec44fa9a7ac6dc63bcdf9a173de5e7fb55ef40f60e97
pdf-font-stream PDF embedded font (sfnt) at offset 0x134B5 10736 bytes