Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8e039761de28b3c…

MALICIOUS

PDF

112.1 KB Created: 2021-06-20 01:50:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 39a6dbdada643cadfc56707983ea48cb SHA-1: a88ebf9d5a446746aece96773dd2611f4a2ad231 SHA-256: c8e039761de28b3c9961444b47e294fcd3b9e51d23b43c27ad612a910d0620cd
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains a large number of external links, many pointing to PDF files hosted on compromised CMS upload directories, suggesting a link farm or distribution mechanism. The document body is heavily obfuscated and unreadable, but the presence of numerous external links indicates a likely attempt to direct users to malicious content or for SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://www.deep2001.com/images/library/File/larefinedudafivure.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/51jr3q10tb8qu5fbfvs4t2tn8j/66454854307.pdf
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/2ba80fef08ed0cbe88b4aa137f8b4be1/78778801258.pdf
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1609625d9c4201---sijum.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160983f0887ad8---vowawawe.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/8141c08b48e8cd1be723a4c5bf13cc43/sezopekexu.pdf
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/njpq3dadffnvhed5cms3vl2vug/18122939479.pdf
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c153be559ad---40331459701.pdf
    • https://chambredhotes-savoie.com/ckfinder/userfiles/files/76006755396.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16098bcd35bb0a---28592501923.pdf
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/6s6bg763v5dette1kddn6rllpg/57664966224.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f58c92108---nenagodivorojoresuwapire.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8db30839e---xunokisupemil.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=amara+heads+and+skins+borderlands+3
    • 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://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015277.bin
bc4a34a6d4ea5b3c44d86347c30576f968d347bbbd03cdc71023a33d51a9ddc7
pdf-font-stream PDF embedded font (sfnt) at offset 0x15277 5128 bytes
font_01_sfnt_off000163a6.bin
a8c7b05149fa22fc633ca9618a84e5cc0d2e1cff2558074c1888c9916b64ff64
pdf-font-stream PDF embedded font (sfnt) at offset 0x163A6 12796 bytes
font_02_sfnt_off00018ee1.bin
3b60b84f554398af14c4ebb484939287515345ca9e6929e6e2fbb436f7be1588
pdf-font-stream PDF embedded font (sfnt) at offset 0x18EE1 16208 bytes
font_03_sfnt_off0001a420.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A420 4324 bytes