Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3d8809e389929d9…

MALICIOUS

PDF

84.2 KB Created: 2021-06-25 13:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aa66b882686d14e4a1e1db2724c2e4c4 SHA-1: d5fc06909fbec130772549a8e3cbd2d7e8be2ca7 SHA-256: a3d8809e389929d96e4a1b2826d2e33f908687490a3aced6ed60dca55675f3b2
156 Risk Score

Malware Insights

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

This PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Several heuristics point to the PDF acting as a link farm, directing users to compromised WordPress upload storage and other potentially malicious sites. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose, which is likely to facilitate phishing or malware delivery through the linked compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/9a926fae3c388c46e6d48141548aefad/70452755729.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5d663467e---bulag.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/s6mnmvtu4rig0f9kilbg4d19j9/11886301251.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c6356c0d4---63382666319.pdf
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfb4c58680---peponalaw.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a9f6a781fd---bijakedatavoletosal.pdf
    • https://suma.ca/upload/editor/file/54926729827.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c1ebb48b5dc---45840540140.pdf
    • http://adbuffalony.com/uploads/files/metotedisetude.pdf
    • http://groupkaishan.com/d/files/99938136950.pdf
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/jhkqnt4sva3b60qjjscl3929f7/15669841850.pdf
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/uoi8k6fuf0u82hdndjb5gtts5o/38056120230.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/9e5c44b3d462b43c4c5e48d7a75ef047/fozalox.pdf
    • https://fanaf.comarticle_ressources/file/jozukopal.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3b711d6d1---7389282584.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16084059e22750---zunumukumes.pdf
    • https://xn--arbeitskndigungsrecht-best-5zc.de/userfiles/file/pawexa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=residuary+clause+example
    • 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_off0000e6e6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E6 16792 bytes
font_01_sfnt_off0000fef8.bin
71749b4affed873eb17a694c8eec16d571385d1d7fd3c59674713134792fbd85
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF8 17292 bytes
font_02_sfnt_off00012bcb.bin
951f4c20afa85d2d08bd1a14e506f115d5a2096532841ad84c041f335f8edc47
pdf-font-stream PDF embedded font (sfnt) at offset 0x12BCB 10716 bytes