Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5cc40e9bb8f427f…

MALICIOUS

PDF

81.7 KB Created: 2021-07-31 03:44:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 7e3bd5fe1bcf41630ff75668f2db5107 SHA-1: 0a87098eb3f3edb6c67ebe484e187de2aee7ff89 SHA-256: c5cc40e9bb8f427f415b85adf692a200182211598963ccfbe99aef5bdc69aa67
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites hosting further PDF files. Heuristics indicate this is a link farm designed to direct users to potentially malicious content, with ClamAV identifying it as a phishing trojan. The presence of multiple compromised CMS upload links suggests a coordinated effort to distribute malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607dee6a0ddee---fesepubixut.pdf In PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/167ecd74845752aa0b1196a308586015/busubonexoxazetitifamuda.pdfIn PDF document text
    • http://michianaorchidsociety.org/clients/2/28/2832e32407c795c8d28ffe68102aa18e/File/655054931.pdfIn PDF document text
    • http://abpaluso.com/upload/file/5988003408.pdfIn PDF document text
    • http://longthinhphat.net/uploads/files/96273076186.pdfIn PDF document text
    • http://hk-dcc.com/wp-content/plugins/super-forms/uploads/php/files/qua05ap90omnb93lc6a2cocanu/senumejag.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/oghthkr2aelb030gvp5s5tmeo7/putobaxogedevipuwiban.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cb985654ac---30142476843.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/a5ec94d0e3f0be41761cb16a846f2b98/nezesabigedu.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a23c2105444---1599702394.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087e2ad6d5f6---walifobixebe.pdfIn PDF document text
    • https://circolodelpistone.ch/userfiles/file/82767588028.pdfIn PDF document text
    • http://bettynblue.com/upload/fck_img/20210515/file/34425188455.pdfIn PDF document text
    • http://wagnerfamilyreunion.com/clients/866685/File/62778283401.pdfIn PDF document text
    • http://nkmate.com/FileData/ckfinder/files/20210727_8177A88AF3E9A764.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fa770069fe4---64259662675.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607131f4035ff---38267559495.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074688928cbf---tenezam.pdfIn PDF document text
    • https://congchunghadong.com/uploads/files/87099962375.pdfIn PDF document text
    • http://mywayrtk.info/userfiles/file/7147693805.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/071c15f6aae490b78a4ca7d342b35077/64209389033.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=download+clash+of+clans+hack+for+iphonePDF 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_off0000da2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA2C 10800 bytes
SHA-256: 5c261811e8a056613f0716ac2cfd7dce908edbb589273ae88112392938a92f8c
font_01_sfnt_off0000f302.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF302 17516 bytes
SHA-256: 6a4d1ace16118bb2a116c0d49bd7b2b0cbef376fed405f32cc7da59afd9adc4b
font_02_sfnt_off000120ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1