Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfa8c59515a4d063…

MALICIOUS

PDF

107.5 KB Created: 2021-06-26 17:48:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 77f3ac0bfeb1d7f966294077ac619fea SHA-1: 5fbd7032e37f9ce174b10e886b736484b2b329e1 SHA-256: dfa8c59515a4d06336703cbe4a10b6337751fcb675595b84b2e08a668c88c7eb
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to manipulate search engine results or distribute content via these compromised sites. No scripts were extracted, but the PDF structure itself is indicative of a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9797

Heuristics 5

  • 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://auxerretv.com/content/public/file/majipupilizo.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc1691768b---mebamoxezesas.pdf
    • http://gesundimjob.at/images/content/files/botubivum.pdf
    • http://kaies.cn/upfiles/210603164002567171y36e72.pdf
    • http://asokmontridental.com/userfiles/file/notizenipovize.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a0e6d5154---83029815158.pdf
    • https://aiaciran.org/cache/fck_files/file/jerukiwivavibus.pdf
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/d50b695b12a81c919c6e52894a9caca8/41388815217.pdf
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160877f67a82be---mobopur.pdf
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9f19d82dd6---74243580132.pdf
    • https://lastcallslc.com/wp-content/plugins/super-forms/uploads/php/files/8da63dd143f25aa920df9c5d65a93520/11525728245.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/j2l9udlgc65d659op6p16ql971/bugipojibonarigujoz.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/1f310f8a70d85b1f9e2e2f5408939030/wijudopuruj.pdf
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/b327cbcde79c103491d60cb6ce2e5d8c/94252059355.pdf
    • https://asthasupermarket.com/userfiles/file/rexenofusobewuvag.pdf
    • http://movementlab.dk/userfiles/file/gukubajumipexob.pdf
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/3be6d4f303acf863e92fe67cd9f29e6e/nabitikojulopelimabiso.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16095fcbc33574---gutukisofodi.pdf
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/a0b21d60a1cae8f208ca28d2e2ce10d4/teleresofav.pdf
    • http://fygl.net/uploads/file/190341338049.pdf
    • http://sarljarry.fr/userfiles/file/80563937165.pdf
    • https://x-software.cz/data/file/93875885695.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1608e36322c0a3---9024405962.pdf
    • https://dijitalsanat.link/upload/files/71109961833.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/961a2726faf733ebef7edd7c6ed42809/ledagew.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160873f3f8273c---12928321007.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=sheep+in+lambs+clothing
    • 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_off00013efa.bin
81402011267b555ddb6482f2726fde50c36dacd9924aa192b138b5892feb0769
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EFA 18176 bytes
font_01_sfnt_off00016e26.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16E26 16792 bytes
font_02_sfnt_off0001863d.bin
c37536c12e19d8c2aaa1bfc010d843097df9dc477f7d8af2fcd46c218542330d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1863D 10936 bytes