Malicious PDF — malware analysis report

Static analysis result for SHA-256 23c1a15018de72a7…

MALICIOUS

PDF

81.2 KB Created: 2021-09-19 04:19:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5d6b6f41dd2a3f3ec103f93eff2c0d7d SHA-1: 8110e711fb1f3916005aeb9ebbcceaf703afd688 SHA-256: 23c1a15018de72a7ed7d06288ebcd64e0e5872a7de52eb2181e204365936b67f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on compromised or disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The embedded JavaScript may be used to further obfuscate the malicious redirection or exploit PDF vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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=6+dot+pattern+lock+combinations
    • https://byocamacho.com/ckfinder/userfiles/files/somuginur.pdf
    • http://budropol.de/Upload/file/75119236181.pdf
    • https://southwestlooms.com/admin/userfiles/files/67493139785.pdf
    • http://journalofcritique.com/ckdosyalari/upload/files/8753013507.pdf
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/30b25ea149d8e7add14c9f1059cb7334/kupafawiwoz.pdf
    • https://1877painters.com/FCKeditor/file/xibenajewetifek.pdf
    • http://inannamsao.com/uploads/files/werebateviviwigunosiboj.pdf
    • http://amunt.madteam.net/ckfinder/userfiles/files/vokajesolologovi.pdf
    • http://jjburgerut.com/uploads/files/bevumevunuvuzuli.pdf
    • http://retrolondontees.com/userfiles/file/22489458894.pdf
    • http://hiroshima-teishaku.com/userfiles/file/56889635173.pdf
    • http://xfswchem.com/upload/files/33995803461.pdf
    • https://ecableapp.com/FCKeditor/FCKimgUpload/file/78697432159.pdf
    • http://cupta.org/userfiles/files/20210902182735.pdf
    • http://kite-surf.sk/files/50667620999.pdf
    • http://twilaw.com/files/files/19266536580.pdf
    • http://www.scea.edu.mn/ckfinder/userfiles/files/fuvajirizere.pdf
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/mfru2sdef3m14j18lr8cbo1097/65086119204.pdf
    • http://e-restauracion.com/app/webroot/files/uploads/files/35165599326.pdf
    • https://transmar.biz/ckfinder/userfiles/files/29873783225.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/161397ef6a8a17---bajuwaro.pdf
    • http://coniperfumes.cl/js/ckfinder/userfiles/files/86462168381.pdf
    • http://instant-image.net/UserFiles/Site/File/27701008402.pdf
    • https://egokituz.eus/files/galeria/files/kunatujevumilegizefipoje.pdf
    • http://igigeothermal.jp/userfiles/file/73832709528.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_off0000d5f8.bin
3bc238da2c1527154c984bca6660f3a05e6d2dbe602d03e0c7f1ebf669b9dd23
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F8 18448 bytes
font_01_sfnt_off000105a4.bin
57b0ba0815af9e1ee891e5d33c02ea01f9258d19c0bf494166db6580492fda0a
pdf-font-stream PDF embedded font (sfnt) at offset 0x105A4 10980 bytes
font_02_sfnt_off00011eda.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EDA 16792 bytes