Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfa9b36b90e21054…

MALICIOUS

PDF

81.7 KB Created: 2021-06-28 13:58:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea0b4981a196c33b9067c322d6d8a26c SHA-1: 48cc89d7beeaa81ace979a079c72b641c76a7a0c SHA-256: cfa9b36b90e2105424c0181a271c705fc75fdb0650fb17d062d695150cfd7dfc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress installations. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms, suggesting an attempt to manipulate search engine results or distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://pistant.ru/uplcv?utm_term=nyu+law+class+evaluations
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c2dda2805d2---fusev.pdf
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9202911b04---79628876739.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3dedf224df---95220804341.pdf
    • http://thermogroup.ru/uploads/files/37805156693.pdf
    • https://tckontrola.hr/files/bekikodunifutodafenamaga.pdf
    • http://brainbond.ro/userfiles/file/godonugelisaxabegovinol.pdf
    • http://al-bandak.com/userfiles/file/67909529342.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/4aa660f20f6649caf295ed07df7df6ec/dukumesuvaxugubilagu.pdf
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071daa0140b7---88898486399.pdf
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160aed7bb7958f---11905836625.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46a9a45156---bopisorilugag.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/bea7bce2a1a4453e2e0f0a20a8e0abc8/kubejaxisakagana.pdf
    • http://brilliantsolarpaneling.com/userfiles/file/niwozoliwofelexa.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607a955c58963---xobosasavarizuwinususefu.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/dv6ts01i6hicspcjekjdn2q4tq/zaginisajageka.pdf
    • https://poolpoint.be/uploads/file/15881288295.pdf
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/16087ba827df28---gofezi.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca5900f5bb---fenakazegen.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/cf84f0a200243e751c32dd3022e320c5/xotojun.pdf
    • http://yngc.ru/admin/ckfinder/userfiles/files/57307953471.pdf
    • https://bawaniint.com/ckfinder/userfiles/files/45929270592.pdf
    • http://ashioke.com/images/library/File/8259811214.pdf
    • https://soechi.com/userfiles/file/15209997306.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_off0000db25.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB25 16792 bytes
font_01_sfnt_off0000f33c.bin
e054f4fdc781bd1f381a37474976a58592a9f71c7da8ca78077af5381907c931
pdf-font-stream PDF embedded font (sfnt) at offset 0xF33C 10468 bytes
font_02_sfnt_off00010b3a.bin
236b4e469fdd894c0cf736cc0b572dd05740c5ccc9f2c89d0d4b173eddf185a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B3A 17640 bytes