Malicious PDF — malware analysis report

Static analysis result for SHA-256 a850d9a995fe66e1…

MALICIOUS

PDF

85.1 KB Created: 2021-07-08 05:38:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a770c42fce0b0075217bd15f5899ee6e SHA-1: b89fa6e1bfac57b1af6d8485e8f6d995cae18a5d SHA-256: a850d9a995fe66e100762e953285a8d274170e9148a67db1df7b3d1db21d7b6e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload directories, suggesting it's used to host or redirect to malicious content. The PDF structure and link farm behavior are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16080ff73c46a2---femoluvuxamododuwej.pdf
    • https://mclandpin.com/calisma2/files/uploads/44996646146.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/f280339c660c7e51768ac44e1a07d47f/82080164296.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/1501790dda659b9edaf987f4de15ba50/bonazumesibunajudux.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba551d39269---75392189578.pdf
    • http://anatolianlgs.com/userfiles/file/bozikudolenim.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/g4dupnk9ja2t4evrce7c3o0qgf/3776362796.pdf
    • https://mygoaltv.org/ipp/images/uploads/files/zopabofiwoku.pdf
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/v3a8ge84llj4bb4gsavtvgof36/1080302973.pdf
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/8f19ce5e298921e70b6a07b4a642b9f5/tebowive.pdf
    • http://nanoscopy.ru/uploads/files/93135452584.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094527d4084a---xobawuxujurutapi.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608842ed6b7ca---98029165794.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/c3c5deda1e6244a0d4b26a6535bb3902/dajaxuwogefafazibefeses.pdf
    • http://studiostocchi.eu/userfiles/files/xosumovetejetunag.pdf
    • http://euro-ex.net/images/blog//file/16808233378.pdf
    • http://ajtoablakcentrum.com/_user/file/33543246186.pdf
    • http://salsainkonstanz.de/media/files/81438949350.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4a57646098---latinidixefawugajorub.pdf
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/18cb1d96bcc393c9e9d5ea69c2ef5571/xivoju.pdf
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/349098a37968ff18d573076248dd3c44/60367226847.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1fbf7c91f9---werevix.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608395c06ea81---vemaz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=squint+treatment+at+home
    • http://irodori.kir.jp/files/file/tolodofojijudomeliboba.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eae1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE1 16792 bytes
font_01_sfnt_off000102f8.bin
5e0d7985bb4515f31b8ac0fdab2916bdf94b6171a1f96ffbff4f95faed3ee184
pdf-font-stream PDF embedded font (sfnt) at offset 0x102F8 10480 bytes
font_02_sfnt_off00011a98.bin
c9d0a4e0f4fc36fdc2ef9b622f1b9cb29d51163249e7ed13d303a3736fc30fcf
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A98 16508 bytes