Malicious PDF — malware analysis report

Static analysis result for SHA-256 c90694efc63462a0…

MALICIOUS

PDF

85.5 KB Created: 2021-09-05 10:52:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ff3da805721fe0deaa111f8d7674763c SHA-1: 6870a89fe6a08dcc6d9cccd07fa3477404a50224 SHA-256: c90694efc63462a0efc14e6c805fe52daf224b8e60a498f377bcb312043756a3
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to other PDF files, many hosted on compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary attack pattern involves luring users to click on these links, which are designed to appear legitimate but lead to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://grandinhr.eu/images/user/file/66863030698.pdf In PDF document text
    • http://sloplast.com/userfiles/files/ruvajulowidakujuluz.pdfIn PDF document text
    • http://chukysovin.com/img-svc/files/82766001109.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/fafe4c50f7ab85e20f1456a4dc375694/fafulitewitixanibigowodaz.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/7ab0bcfdd1c8bf04ac4e7ecdd99a1c02/suvadomu.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/file/1630317535_1.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/a8474e0e40d736926eca095090809e76/87764313422.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3e6239aa8---98404769912.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/161296f5f52724---bolizumavaf.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/83520841948.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/ad15a5332b816aab695cc1556a29e9ba/tukepovutu.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/8f929045a23de2ec54f21a964eaafae1/nazutagaxiluxizugesex.pdfIn PDF document text
    • http://abwlondonblvd.com/uploads/files/duginufitatej.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/60a8865457598c49cf1683312d2cc4c3/lixelaga.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/79ec5d6506f3a56416d0c6ae437a08e9/pixiwir.pdfIn PDF document text
    • https://ncltandatbar.com/home/ncltandat/public_html/dowalumniusa/ckfinder/userfiles/files/rakazerukiwunomax.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7906498ab---vovabepumudize.pdfIn PDF document text
    • http://cleangroupbd.com/ck/upload/files/409353920.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/d0c603ecbef4d326dbafbbda1b289fde/5322535181.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5225e777a---81878052169.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/d93e3518ebbc90c8f370c4bdfbb31876/difelisalos.pdfIn PDF document text
    • http://shipagents.nl/uploadfiles/file/jogakatazakowiluje.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/e3940858e2b9c5e7e37d8280461730e6/zudakirojefun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=emitter+follower+theory+pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD7 1872 bytes
SHA-256: 79be395588af96fa5df472893822587051e439780fb3f760348c77be68f22830
font_01_sfnt_off0000e58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58D 10512 bytes
SHA-256: 689a79b25ba2f991c6cdf28c08127333d5fad0de11a3f27a4f277cb0c323c1f9
font_02_sfnt_off0000fd71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD71 19300 bytes
SHA-256: 85cd37edfe25fd6cf73914e7fa73bc1e10ab9f5ddf5e6f26450296112c19aa6d
font_03_sfnt_off00012f7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1