Malicious PDF — malware analysis report

Static analysis result for SHA-256 d44d5bbb15b4e6cf…

MALICIOUS

PDF

83.3 KB Created: 2021-07-01 17:43:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1c28720d9838b9361db1aabb3dc1fc56 SHA-1: 9ca6a721f5b0908179d9cc08692fb1fa3306fdc3 SHA-256: d44d5bbb15b4e6cf983f1b32593a78cd7bd9da8b0f48d036f8593a5643713896
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple distinct hosts, many of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of numerous links on disposable hosting and the use of UTM parameters suggest an attempt to obscure the final destination and potentially improve search engine ranking for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://studiobaliva.eu/userfiles/files/lazuvuvedopudufidu.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/d5adbcaced3aa297b20289d1ff5795ec/44236935394.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/ovvunp2nhnpjuasjf891svrs60/fojiroguzemikenetuge.pdf
    • http://teplospectr.ru/images/files/89491981471.pdf
    • https://chris-arnold.com/userfiles/file/venusukesugot.pdf
    • http://vintageguitar.ru/ckfinder/userfiles/files/53568430165.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1608471ef9d3cb---16729169782.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1606c879783505---piwitekogilumafakitora.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/d9e492d365b0aa16397873641d320e30/wadamawedofozuduvofedaraz.pdf
    • https://alakharia.com/public_html/userfiles/file/jirapagilola.pdf
    • http://drive4smilesontario.com/clients/e/ed/ed023a0734c265ca673a92d1d81de675/File/pematevin.pdf
    • http://n2nlah.org/UserFiles/file/velojemupasozipedafur.pdf
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/691d3a750643eb0a218ce1ad93d25436/73879238167.pdf
    • http://biswasi.com/userfiles/files/94600655822.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1n2rofrk0av70r4revvq7kgr93/mexek.pdf
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160b5a84641641---22379262430.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/a2ef520b581f26e31cd3463dbc1fd0b8/laxadijuri.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/mhengtv9apr3ilao848p9abpsj/75297636068.pdf
    • http://isosklo.cz/uploads/fewupokixubudug.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/4cfd2eb4d56d159d63e1b9bc18e46483/60077224172.pdf
    • https://ottenburger.com/userfiles/file/tilade.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078499de727f---4659645069.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/dc2016074a0c065bbeda1c141af3e4b8/5154705950.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607d770d295e5---nemubajejevinogopowamemu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=the+storm+sister+read+online+free
    • 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_off0000e340.bin
f4a3d18f9df0a66c7367eafea434292150999d84d36b19d7291875c97764d475
pdf-font-stream PDF embedded font (sfnt) at offset 0xE340 10584 bytes
font_01_sfnt_off0000fb38.bin
3c9ed94109ba1a7a2420b8189d1f380dc837920a797f6a6e43d5d34aba154642
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB38 17112 bytes
font_02_sfnt_off000127e6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127E6 16792 bytes