Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8491d76e2abc040…

MALICIOUS

PDF

84.6 KB Created: 2021-06-26 01:54:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ffbf80cc8cfda7533f30bc64f6f649b6 SHA-1: 2a15f09063c49b55bca05ff1e5c7341c3784b4b1 SHA-256: b8491d76e2abc040550c6b0a4e3fad4aedfa7aa340ca5c4506548379ada1d867
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the presence of a link farm is sufficient evidence of a malicious attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c33542590---sinuweboz.pdf
    • http://birzebbugastpetersfc.com/files/file/39296033735.pdf
    • http://bagiez.com/userfiles/file/27689496382.pdf
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/b15d68bd8300c2d99d0eb9cf7922db5a/58370767604.pdf
    • http://mauchlineware.com/html/chapelstreet/web/userfiles/files/sagifulimukuwimeja.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/d5b76030b8b8b5a61d95254b5c8a9827/pivuxoraduwezisak.pdf
    • http://zeguvietnam.com/uploads/ckfinder/files/sogitavotukedisimo.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/e850efeede26b7f0a38297437e0a938c/toxanesudexekizo.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/0baef244d9b56a5322eee2fa116719f6/difasatogelat.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f992c52d33---15684331859.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8b67240ed---maxarabulikovupokugar.pdf
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/nefn0sar2qe5vk8ugdj1q4g5v5/43773175093.pdf
    • https://cplastik.com/data/cms/file/40019911309.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160717c7d6fceb---82752429339.pdf
    • http://rotang.net/userfiles/file/56736985336.pdf
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/58cb8fd2d2add4ef32841517ce6f8470/pumizevafisawakawerute.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/9099aa0728b3b96229c0bb274fb15150/92766418401.pdf
    • http://lagunaapartman.hu/images/user/file/16010272657.pdf
    • https://burgas-remonti.com/userfiles/file/72800996238.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1608c89320b8db---gupotavumajos.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/2ce8ac9847c3879d31f491277130463d/17579154601.pdf
    • http://educationexplosion.com/clients/a/aa/aae59ec6301d25964842a0067e0ae100/File/65586286784.pdf
    • https://gyandeepjkss.org/userfiles/file/89084635254.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/76bb19236cb26539aee73d9421af4008/25735545351.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d5798eb85---wagowu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=reverse+charge+on+gta+under+gst
    • 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_off0000e724.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE724 16792 bytes
font_01_sfnt_off0000ff3b.bin
a252b33a252a8cafe48af4651df8e41d99c48fb5466d2004fe36e88a9187db3c
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF3B 10724 bytes
font_02_sfnt_off000117ae.bin
7ae218a5768f27e3c7eb7f8f94c6be792a9d3058bef00c882b018343f8df229b
pdf-font-stream PDF embedded font (sfnt) at offset 0x117AE 17260 bytes