Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5a253af1c7d4e6c…

MALICIOUS

PDF

84.3 KB Created: 2021-06-26 00:26:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fef4e9a10e6d218a81e13f2c109278bf SHA-1: b61392ad5df430997c113eb648114edcd01f1cd1 SHA-256: f5a253af1c7d4e6cf92a20db73717ee3a4ae1034a46d79f36c13cc5279a7084c
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites hosting other PDF files. This indicates a link farm designed to redirect users to malicious content, likely for phishing or malware distribution. The ML classifier strongly supports the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/56d82ae06a7dd8a9f345404e6e0b5d3e/4012923221.pdf
    • https://cvsc.co/userfiles/file/visurisuvekozagatumixi.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160749a7b23e92---kogigafiwujanenifulefizaz.pdf
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/d102409a50826afe09a765a301aaba78/varovelol.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c8efdf4b44c---tugapuxexilotirob.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc2a8cca6d---lokizigarozozobuxoberuwe.pdf
    • http://jarosi.hu/files/file/vomulitareli.pdf
    • http://debeleven.net/UserFiles/File/fetovezujusobax.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/14eaac59c776ad09ce2824471792fc53/dibakalabiramufokizatefe.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afb3a34b788---17751995518.pdf
    • http://madmojo.com/fckupload/file/79905906019.pdf
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/23177599836.pdf
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/b2fe229a2d9da39b112383447392fe57/80063448637.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160961f144af88---93772275471.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/pdl4fdatc390pg1r5tl7lb4ben/xemogiruwidi.pdf
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa163642948---loremiv.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aabefa4da6a---76484279673.pdf
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/5qa3la9pick4rea01f7i6drmvp/gosemawuzomerexoku.pdf
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099dcdbae815---xeduf.pdf
    • https://itacademyindia.com/ckfinder/userfiles/files/36086002206.pdf
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/71m57it086pveojos27b7223hc/rexukojozifun.pdf
    • http://aldo-ins.com/userfiles/file/bekazuvipuvirepo.pdf
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/d44c64a3aff6de611b4d77ca1c047bde/nexevebalofako.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=octave+bot+discord
    • 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_off0000e68f.bin
3bdc650f4da6b00d1bb62dc1072a0ddbf2cda19d9db9afd5f0e68f04c6b6f69c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE68F 10444 bytes
font_01_sfnt_off0000fe7a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7A 16792 bytes
font_02_sfnt_off0001168c.bin
8df55d58afc26fe54c5bbd46136396bfa2b5b9e5054cc6534319870835057b98
pdf-font-stream PDF embedded font (sfnt) at offset 0x1168C 16924 bytes