Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd58db4c75126e1a…

MALICIOUS

PDF

92.3 KB Created: 2021-06-27 07:38:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0ae045d99abcaf44760973ac081d2a94 SHA-1: 4f2b3ce195d7e70958ae867e896c5db78646b1ee SHA-256: cd58db4c75126e1ad060ae5422012d149bac437029b44c96fac905d695aeda4b
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to unknown files hosted on compromised CMS uploads. The ML classifier strongly indicates maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/ab6b78c2fda9b70e095762f04580cf32/1333124185.pdf
    • http://profil-metall.de/content/uploads/file/90067718973.pdf
    • https://adepotcustom.com/UploadFiles/file/20210606090753131.pdf
    • https://nnkcreations.com/userfiles/file/sujujebidutinelutekor.pdf
    • https://dineflon.com//files/zoxolerozawopobuvi.pdf
    • http://babywagen24.de/userfiles/file/63923476677.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c908f5ca8f8---vevexakosijimonogenaz.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/a85f9a4cdf426d4aac7d4fe0022109c6/jizixivogagipesekubatixod.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/n06h9qd4sg8splb300fl7mngib/62323481149.pdf
    • https://dewalt-naradi.cz/media/upload/editor/file/fewobixuf.pdf
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/5566673104.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/e6d40a654b343e749e828a5c2769d1cf/1263791182.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096b78adab82---40554133398.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086b6c799f6a---16336975387.pdf
    • https://debcopharma.com/userfiles/file/pevefuwovonujotugofe.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e95fe2e0bd---77833238294.pdf
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/4bad2ac0449182193dcd784b9e660a4f/likawetikotaxe.pdf
    • http://re-view.online/fckFiles/file/botepodapakajoxodot.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/be24cbb1c0391191460e843210095b3f/44008581042.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/84cfdbcf1de49d4b39a73cf063c6d6e3/duzolub.pdf
    • https://alatheir.com/atheirwsfiles/file/fuledapedajexugi.pdf
    • https://aviatroglo.fr/IMG/file/divimoba.pdf
    • http://kipia-nn.ru/userfiles/file/85360500759.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=sequence+game+board+pdf
    • 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_off00010497.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10497 16792 bytes
font_01_sfnt_off00011ca9.bin
255739cc82442b8b205ba8f022fbe1bc263b7c2bb444b538a487ab8a367612ba
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA9 17964 bytes
font_02_sfnt_off00014b7f.bin
c3b62dd3b61b4c1f89f8f35a65d9aab34ae855a277c901d1194e243d5f75f39e
pdf-font-stream PDF embedded font (sfnt) at offset 0x14B7F 11020 bytes