Malicious PDF — malware analysis report

Static analysis result for SHA-256 87e305bdc1664e34…

MALICIOUS

PDF

90.7 KB Created: 2021-08-02 16:00:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f9b52f97c69eb9aca0c5c97c507f4cf0 SHA-1: 4b6c6b9ff71958a41d8eb53b304112a0e58e4a5e SHA-256: 87e305bdc1664e342b1a954a3aed7bb10d39d660c3f73dffecdf8f4753aee4f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the link farm and the PDF's structure point towards an attempt to exploit user interaction via embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/hli2lae6e6cro7hmt14duislf0/xuludopidorafiwelilubuv.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd22d7569e3---44051901083.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1607a4403209b7---98238599528.pdf
    • https://zagorjeadventureteam.hr/files/64327556361.pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eab02b3718---89305396505.pdf
    • http://highendschmiede.de/highendfiles/file/zanujebokobubave.pdf
    • http://vuatoyen.com/uploads/userfiles/file/17116363756.pdf
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/dc270f6f7a7beb95f188deb2644b7c77/jilojezex.pdf
    • https://anmimar.com/royal/userfiles/file/vesuw.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16078def9cbf40---gepeboxezume.pdf
    • http://axiomestates.com/userfiles/file/wujotazisupopatalujumat.pdf
    • http://golden-candies.ru/webroot/files/files/kutuduvojifeve.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baec80b161b---12305726099.pdf
    • http://berrybucs1973.com/clients/3/3a/3a2d6910be1067feaf6dc79f90d505e0/File/33022311413.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/2bcee8211635d56a68391bdf0d6a9718/xivubakisef.pdf
    • http://mebco.ru/images/file/sevix.pdf
    • http://aceonlinementors.com/userfiles/file/92136162675.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdb2f98877e---jokologipipesobotavur.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=problemas+resueltos+tubo+de+pitot
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e0f3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0F3 16792 bytes
font_01_sfnt_off0000f90a.bin
1c54c2d276c49ec799fb3b58a527b53a2e9d1ff2149337b1ac7d5930d07324c9
pdf-font-stream PDF embedded font (sfnt) at offset 0xF90A 10692 bytes
font_02_sfnt_off00011151.bin
d8eb9e5a9afd532da8fc742717be8448fbefa53996a5075c1d018c695c10480a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11151 20252 bytes
font_03_sfnt_off0001465c.bin
7384f78f7eee0a7747af6aa54f6a012ae917b773c3daf511a94379393b43df11
pdf-font-stream PDF embedded font (sfnt) at offset 0x1465C 16144 bytes