Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4f287857cfba690…

MALICIOUS

PDF

91.5 KB Created: 2021-07-21 07:23:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 516409f920d7553f8a1cb4ad39281c3e SHA-1: a21a2403164ca92afb19331f6f02a3186a042fe7 SHA-256: d4f287857cfba690f0c019d4fa9e33d77004fe9c0cba4a11cb45df47e554437c
156 Risk Score

Malware Insights

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

The sample is a PDF containing a link farm that points to numerous other PDF files hosted on compromised websites. This technique is often used for SEO poisoning to lure victims to malicious content or for phishing campaigns. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608099095f047---wetivi.pdf
    • https://karapinarinsaat.net/userfiles/upload/file/sunaka.pdf
    • http://gocreate.termall.pl/upload/fck/file/talokuzanukiradake.pdf
    • https://guineaservicesproviders.com/gsp/files/wevavowolijamepakuno.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a68a1a35a07---fibekejavup.pdf
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/7cbb6c244c401aca2e2cb8e089dc007f/foxatusukiwuda.pdf
    • http://tillmanfamilyreunion.com/clients/b/b7/b7385abc5988d1ee605fea7695e3d00e/File/kotufezagamatupere.pdf
    • https://ludifrance.fr/userfiles/file/refosulazujeborazafom.pdf
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/cb0f839bf5c7e101eb8a6e706b08e374/56443154099.pdf
    • https://anup.bo/images/files/89774502509.pdf
    • https://landbondcorten.com/attachment/file/3290d7b9c2a5e37e999e9fce48899ce8.pdf
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/13010890977.pdf
    • http://malbreil.com/userfiles/file/vugojomujarinuwogigur.pdf
    • https://ccaquebec.com/userupload/files/30714793421.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb2a191817---wuduzenijimazodorov.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e898c552c4---mozepadap.pdf
    • http://brkvinc.com/userfiles/file/xuzevuparewo.pdf
    • https://gangwontaxi.com/FileData/ckfinder/files/20210709_52330FC4C5E8FFD8.pdf
    • https://sitycare.com/FCK-UserFiles/files/nunanijuwesunusipox.pdf
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/1607c913168a91---wapapogamosefiropuwiw.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a75338c62dd---21730832088.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ad83564f8b0---10062562938.pdf
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077e843b82e2---21183655435.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=tongue+lip+and+buccal+ties
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/3a8e1382e0703a7f813d4a050d00cc5d/53805366975.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_off000103b7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103B7 16792 bytes
font_01_sfnt_off00011bc9.bin
f5f4c855b4b7ad29cf7edadb21cff9a923b044745adaf2731355bcee4f508571
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC9 16976 bytes
font_02_sfnt_off00014812.bin
7aedba76840d668c9c563d2ae4686c56fcb1c9826890d2e6c81f49fc2975e8b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x14812 10792 bytes