Malicious PDF — malware analysis report

Static analysis result for SHA-256 91b63f6b4ea1f44f…

MALICIOUS

PDF

91.5 KB Created: 2021-07-01 17:56:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4168e3387ab7cce0676f2fff89f937d8 SHA-1: 20e4742b6f6a8a41f2d045d9d72ebbfb519f2d2e SHA-256: 91b63f6b4ea1f44f4afbcbb9dc66269c5f1f7fd443c1e60e54481458467cee79
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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://pottoka.info/files/galeria/files/basofafigobu.pdf
    • https://sieompaysdebray.fr/lesiom/txt/imgadmin/file/78492826456.pdf
    • http://sllight.ru/design/img/upload/file/76120293758.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16097a0be21c98---nepebanevafadon.pdf
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/he9l8198d57ptcvke4g9esqbt2/57306069881.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16098546ef1aef---galuzufibijuvusijiwi.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b409d1ce979---5294666330.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bb626ad05a8---80321747813.pdf
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9d7673071---dejevapugomamigilinenosa.pdf
    • http://amandatravel.com/userfiles/file/guzuzeja.pdf
    • https://computerzone.pk/file/lomemekovuzugonalopime.pdf
    • http://kojeneckezbozi.eu/userfiles/file/97469108767.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/acb2d2e08560b8c79fded9a87aa43be3/lepumar.pdf
    • http://aftckwt.com/uploads/file/pixelajeludi.pdf
    • http://mega.kz/media/upload/files/jutirujesad.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160d9e4e62c28b---11512485350.pdf
    • http://marinda.ru/pics/images/file/sudofodupipaxiw.pdf
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/16070a29b52293---4271269374.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c46fdb9bd81.pdf
    • http://mega-gold.com/userfiles/files/juponapivopewa.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/16080b1734d45a---sisalez.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=manifold+meaning+in+english
    • http://s292376414.onlinehome.fr/datas/imgmail/file/kutupekinevejilifukewaguk.pdf
    • 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_off0000e893.bin
11146aef16d9b07a6af655947cc36ef8a24d81592aa3b5d6688248508c3ec663
pdf-font-stream PDF embedded font (sfnt) at offset 0xE893 18928 bytes
font_01_sfnt_off000119e2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x119E2 16792 bytes
font_02_sfnt_off000131f9.bin
59a3ce526636cd7873dac5b701ddf9b75a8aad26e79154a66ac323e385c46e4d
pdf-font-stream PDF embedded font (sfnt) at offset 0x131F9 10596 bytes
font_03_sfnt_off000149a7.bin
8bfc5e2f6383778b4716e60c732a7e5228106b692ca52c1f6b3c0b2892049825
pdf-font-stream PDF embedded font (sfnt) at offset 0x149A7 16060 bytes