Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f6a8c59b0c3411a…

MALICIOUS

PDF

76.7 KB Created: 2021-07-06 01:26:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 365e83e3aea67d21ea9044affef1754f SHA-1: 540306eefd20ce5664b34edaa7ad9241cbd6055b SHA-256: 2f6a8c59b0c3411aaa0e7f4466ab8a7fb662f2b3dc79ce7c60b16e8a0abc18e6
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is part of a link farm hosted on disposable or compromised infrastructure. No scripts were extracted, but the structure and URL distribution indicate a likely intent to manipulate search engine results or redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://vietnam-intraco.com/webroot/img/files/lufomugitapunurorer.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a91c63561---1128016272.pdf
    • http://kurskodkb.ru/page_edit/_samples/userfiles/files/35067459870.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e361a3c476c---16546475765.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/1vhr7l5kcm49ptb80qgpd2a9nt/68659613707.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609a30e4c63bd---86177417389.pdf
    • http://sdds.be/userfiles/file/gatogopowa.pdf
    • http://dansensvenner.dk/imagesfile///62828124720.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/5cd3fa1490ea3bc872f636f6245da662/pedituzikela.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609afe15b5f9e---37881379977.pdf
    • https://chris-arnold.com/userfiles/file/18433574051.pdf
    • http://angkalaris.com/contents//files/gonesifekepef.pdf
    • https://sailstudy.in/ckfinder/userfiles/files/46920480893.pdf
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/l2lf3ea5bgkveg05uif6h99l05/wasokamu.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/1f4c26e4f3d25e6cf98211e3bb47997b/mipep.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e0f6c40c1b2---63650607608.pdf
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/3542493496.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160aed6906a2a4---zajenuwoku.pdf
    • http://teplospectr.ru/images/files/50901406081.pdf
    • http://sun-eko.eu/files/file/71676353963.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/a2e1c79703d8e2d04fca108df13c35ca/piranigafivasuregujazupeb.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad76d96eb7b---tezitawisivinirodivirozo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=oh+holy+night+in+spanish
    • 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_off0000ca99.bin
4003266a7d4226db904985c2e3dd94ac464f6b5bb52dd63d2ced5b9becc667cb
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA99 17328 bytes
font_01_sfnt_off0000f643.bin
b03ea533f1350ab72585b5897061a33b9bd8f61e53ae336c3e8848bf785cbab0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF643 10440 bytes
font_02_sfnt_off00010deb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DEB 16792 bytes