Malicious PDF — malware analysis report

Static analysis result for SHA-256 43df339c88158af6…

MALICIOUS

PDF

75.4 KB Created: 2021-06-25 19:16:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ae5272fb8bb1fd7d87d02127e5c18b82 SHA-1: 3ce5d6718be40a0a83d5013c22c6bfc5372e55a1 SHA-256: 43df339c88158af672d9570980e120ce540538628f2a3a12c0b42822df369096
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised CMS upload directories, likely to host and distribute further malicious content. The PDF structure itself does not contain executable code, but the embedded links are the primary attack vector, likely leading to phishing or malware download pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e239e05cd---58521776092.pdf
    • http://clair-environnement.eu/catalogue_dynamique/file/2883543242.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c79cc1d0a4f---gujusemuwok.pdf
    • http://vasvaripalmuzeum.hu/upload/file/7062826212.pdf
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c6b02c0fbe6---bozavexapitonufo.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16075003097574---zobusijoruwiv.pdf
    • http://rzn-house.ru/upload/file/48497173046.pdf
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/udqegrccfoaa58d54dmli6u3j2/76737672248.pdf
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/a8d702735c7b0df90aaba17a64b3acc6/53544571972.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083c5d0a3fb4---voritekivowofikugeko.pdf
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/17cjb8qghbthlukiupfi1nuhh0/tufegupuzusesujo.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ba1560b4f74---kilavomizogetatabujin.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bd5f683bc1d---41424068612.pdf
    • https://muguet.fr/sites/default/files/file/27719586911.pdf
    • http://wamer.org/userfiles/file/jelajefutida.pdf
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/qr5vsgd3v7pg4nbj27eb5k2lf8/39013767265.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16082563032583---25921341017.pdf
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d101712464---jusukarivonedokaseg.pdf
    • http://angarakshaksecurity.com/userfiles/file/37227137878.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/accee4dd41b858b3524c42cb838f99db/detawakur.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a079dd28d4d---dipubenoxubowa.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b4a5a2c98f5---43512394251.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/8d9e5f0428fbb9b0fcde767b78867c66/marituxunuz.pdf
    • https://www.stjohnhomelessshelter.org/wp-content/plugins/super-forms/uploads/php/files/32c3bab0cc9c2dee3762ad7bb69c2c8a/81763106351.pdf
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608444c9c3a3e---58440255474.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=what+does+canon+mean
    • 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_off0000c17b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC17B 16792 bytes
font_01_sfnt_off0000d992.bin
420e23e33fbc437ed1c72ecbd65537c596da6d560c8d4c6965562865bafe35ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xD992 10388 bytes
font_02_sfnt_off0000f0ea.bin
170433ea27960154b88e5e572ae7f1f5ab11872d33011c8a1d167d79d2193bf1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0EA 17992 bytes