Malicious PDF — malware analysis report

Static analysis result for SHA-256 b38afc8b2566341d…

MALICIOUS

PDF

76.7 KB Created: 2021-09-05 07:54:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 189e9aa2cb6d041eda08a907fa5b18e4 SHA-1: 874c1e1562fbf76eeb00869f5ee119f5e94be64b SHA-256: b38afc8b2566341d41c331e42d2a2057ae2a76e8f1d7ceb939647917d7f93433
96 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous compromised WordPress sites, indicating a likely attempt to manipulate search engine results or redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting its role in a potential attack chain. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific user lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://anpo.vn/upload/files/92034669549.pdf In PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/724af4663e39c1274a8c1b78507b597a/pokanujomoxegib.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607171867d004---8492096514.pdfIn PDF document text
    • http://canvangdientu.com/images/file/tuliwetufasega.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb31490cb2---91068472403.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/33vkffk0vaknbhiubatpilnak9/lonozapowuxifavezilebijux.pdfIn PDF document text
    • https://harom.ro/files/file/tusojuromoza.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/xevubekilufurag.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/7464652224332c3b107152422fc49643/75899000956.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/68009780155.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16123c6e7e591b---28810614932.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0b70046bb---xonadozaliwefego.pdfIn PDF document text
    • http://applecentervn.com/uploads/image/files/koridojofugo.pdfIn PDF document text
    • http://abpjse.news-read.com/upload/files/poxevijobelatasugapose.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/t0c7kmoinlofpdadko48spf1gi/bafuf.pdfIn PDF document text
    • https://airshow-bg.com/file/xupopilesavami.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/5129808881.pdfIn PDF document text
    • http://www.addvanceo.info/userfiles/files/7572717189.pdfIn PDF document text
    • http://www.ferm-matic.fr/upload/file/69872086984.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/74509343912.pdfIn PDF document text
    • http://gagutp.com/sa_upload/userfiles/file/20210531082617.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=international+business+12th+edition+mcgraw+hill+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c6f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000df0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF0A 11516 bytes
SHA-256: be4998ef9c21b196949a306e7acdd80790e63f0ac44b53e523b4b55a14fd83dd
font_02_sfnt_off0000f9cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9CF 16748 bytes
SHA-256: 1c35a08e7ba9837d185d220d9569501992f9dca80263d5234d04ae1b93551f0d