Malicious PDF — malware analysis report

Static analysis result for SHA-256 aca6fb139274ffe5…

MALICIOUS

PDF

85.9 KB Created: 2021-06-29 13:15:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dcd450f10f5a269b7f46f52c1dfbb1d9 SHA-1: 11214d39578aa38359e5353f68083b4745f23c50 SHA-256: aca6fb139274ffe5af2669508f57960cdc9d09cef6bd4300e8ee53a5236eb698
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. Heuristics indicate it's a link farm on disposable hosting, and ClamAV detected it as Pdf.Phishing.Trojan. The ML classifier also flagged it with high confidence. The document body is heavily obfuscated and unreadable, suggesting it's not intended for human consumption but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/hfnvnihn2113q9sh9tqek0lq96/52267741618.pdf
    • http://animationcoach.com/userfiles/file/nadekunerotuzusidafamimub.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/qvma0pvrc9a52rncik1i4biqra/mupakesilif.pdf
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0a7459cde---2709982412.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/160bd831f0e2d0---kepigadugumakujox.pdf
    • http://supermarketdv.ru/files/file/1341015708.pdf
    • http://portalcom-b2b.es/img/user///file/_0697097001620338106.pdf
    • https://almondzwealth.com/administrator/imagetemp/file/bapaxoxudaxozeravelemexok.pdf
    • http://mulroyenvironmental.ie/userfiles/file/17433281099.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1609696a5433d5---surataledaramulameba.pdf
    • http://flygarfield.net/userfiles/file/80920308712.pdf
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/71f49da27a51f6f1db5b4714750b5da1/7309898199.pdf
    • https://csodamalom.hu/files/files/goradojalev.pdf
    • http://chokmanee.com/userfiles/file/sipazexivakadugeloseka.pdf
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/nq08kvp3r0gljm0bhk12583if8/81739452913.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/451d27aa358835c8a9c719fdc1f2d233/22834033022.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/018445a38633d1e8e9757ed67258eb54/tapagogari.pdf
    • http://naturalmis.com/userfiles/file/nutavapobakafat.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/811f8a183f4070cfd33855302b92bfe5/boxanozel.pdf
    • http://mitsubishilongbien.vn/images/ckeditor/files/2475935204.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/e98209a596cd8612f0075ecb37b870b2/tanorid.pdf
    • http://anandamsanyal.com/userfiles/file/lepubuzemikekavuwalixi.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/a3306a6872dfce0992b61778bbf15391/gepufudazenebilad.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d1ad08e08---667160294.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/a45e491be3b8da39840848cc5d90dba5/46753126922.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecd7e68370---26099094286.pdf
    • http://tortsurprise.ru/upload/redactor/files/62642473224.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=will+allow+me
    • 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_off0000f05c.bin
8e40cdc70defb7e8d2fb4d66b60096f42c8bb0ecf9d7ef0386578a4cd49898ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xF05C 9880 bytes
font_01_sfnt_off00010622.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10622 16792 bytes
font_02_sfnt_off00011e34.bin
a3ab3bce2ec0a06d39d8c659ae28ff0d1699cd0ebcbde521c7463570385c3e38
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E34 16888 bytes