Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d8804dfeb238863…

MALICIOUS

PDF

90.8 KB Created: 2021-07-03 15:55:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d0ad500bb08cc22966eff0bfaff0e871 SHA-1: a56410d19631101b7d0a8a706792719fa22d882f SHA-256: 9d8804dfeb238863758fd6b0d6d5b400b356c7eecbcb54f7f9891e57cc666ba4
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, with the latter detecting it as a 'Pdf.Phishing.Trojan'. Heuristic analysis indicates it functions as a link farm, containing numerous links to compromised WordPress sites and other disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 6

  • 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.
  • 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://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160872fb558042---34813690434.pdf
    • http://sarlampa.ru/upload_picture/jorunawijoj.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/2ncmni4vsti3of8c5pp06ph8d1/gugux.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ffee1k8c52a5680q2bb5nrdbrm/memajuditotemukoritepigob.pdf
    • https://machnik.net/ckfinder/userfiles/files/86309823744.pdf
    • https://lapalettedesarts.fr/gestion/file/62321074001.pdf
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16075afac133f4---57461817245.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/5c28b91992af0af1781bf2a9332f29fe/4306204421.pdf
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/21m30n2rhn1irrqesri3tn4jva/nuxulikaligiputazakitil.pdf
    • https://mfdesign.hu/files/file/72710617894.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074805258ee1---97901763718.pdf
    • http://phuocthuan.vn/images/pic/file/temiwulo.pdf
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/48f2de079b8e7eff5830fcdb32fa7e84/43716772375.pdf
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607502737c85d---62979178185.pdf
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/97d5e6fb632ceec9ce0fb9056a4fca8e/fidolu.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/5f6c0040b78426383bf3ceeec4251481/64927908519.pdf
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/7a46eff6aeb8a3a070e7d20d591584de/rubefuvewuvuse.pdf
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/55328ca6414b10c83d312371ca1cc0a9/18355405623.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b3e2610205d---20009897765.pdf
    • http://asesorgubernamental.com/images/file/54563610276.pdf
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/5e3k9hcq3c9q4oncibhsp7hliu/88910991140.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160b5a0a50c521---temetavuf.pdf
    • http://contrast.no/ckfinder/userfiles/files/12683280026.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d30bc7362---59274773306.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160add593916c4---fasovafolivib.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/k3emt33n81ou9nr9ssqvvr34jg/15668288353.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=acls+pre+test+answers
    • 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_off0000feca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFECA 16792 bytes
font_01_sfnt_off000116dc.bin
f317e84496617836b265c6d673267f7664b1e9bb10101c02e488aa239c4f7059
pdf-font-stream PDF embedded font (sfnt) at offset 0x116DC 18104 bytes
font_02_sfnt_off000146a2.bin
8131b2e005b7676021a1a7b757e0222adb218dc107b2bfe501eda13aa78c55f6
pdf-font-stream PDF embedded font (sfnt) at offset 0x146A2 10220 bytes