Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3fd5624f51f8377…

MALICIOUS

PDF

85.6 KB Created: 2021-06-26 08:18:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 294d03f79a1bdb7d7a8cec8e123dad25 SHA-1: 0abe64bf5077b053c1b08d2f8195527e122dd301 SHA-256: b3fd5624f51f8377398f4c7dad4f5915a48273e310bc820215077a2f912143f6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript and link farm structure suggest an attempt to redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/a677467e20e035ba73913e3df9ece71a/45181815555.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-5-16/20210516144142887775.pdf
    • https://tenfci.org/userfiles/file/baxenafete.pdf
    • https://craftsmancuttingdies.com/wp-content/plugins/super-forms/uploads/php/files/7cca651d5b9209f5095cc5571bc2af28/21155024930.pdf
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4b6154dd3---rikewepujazimam.pdf
    • https://imahima.xyz/js/ckfinder/userfiles/files/kovosamewofutifujuxinu.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077868bb1ed8---ludexivefazajuxirarax.pdf
    • https://tvsporedi.si/vsebina/tepetigerokoroxavo.pdf
    • http://abpaluso.com/upload/file/ridepar.pdf
    • https://topupdana.com/contents//files/zurogifisoroli.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/30m5am438kuq9u1ibkejeb5m9u/90104437433.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a64b3aeb18e---27114999219.pdf
    • https://anfauglir.com/images/file/20798669719.pdf
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160708f60d99fd---36731812011.pdf
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/63b3b12b69d4d396dfda89bf93832198/nusalogisogaxezovubejetez.pdf
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0172807b8---25894768049.pdf
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/f32c1ogfr9p0qcvej3dahjoa9v/lakoduzowexodovuse.pdf
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160adf2b92c90b---donepazasedufo.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/c574817b30e98bffbc877bd73bcdf2c0/95906336144.pdf
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/611cf84358866de23b524812d79cd568/kijesaronidamuloxoxobi.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a8a0550dad7---nobevedafopuxabuf.pdf
    • https://jbdclothiers.net/emailer/userfiles/file/jokotedimexoralix.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/f59f9ed9df645f020b0d566f9354aee9/19879646905.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/94be304daf38fbe8f72c698e4b4ebdd9/51473616464.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=asexual+person+meaning
    • 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_off0000ed37.bin
d1ddef8904f0dd3a76180d5475e2cdd4413db7ab5dc3e090edbc1f4b4cb98341
pdf-font-stream PDF embedded font (sfnt) at offset 0xED37 16824 bytes
font_01_sfnt_off000118ec.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x118EC 16792 bytes
font_02_sfnt_off00013103.bin
bbdd3e2c9830d2f4dbdf4ed5efdea513b809d5ba47c09f6824648a713782da6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x13103 10680 bytes