Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4aa92c46bdfc565…

MALICIOUS

PDF

89.7 KB Created: 2021-07-05 05:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2ab567a6aeb4a0ba9d07cf10d67c8c7e SHA-1: 5aaff68c010e7b20d70c09f26d2c2d26622b4175 SHA-256: c4aa92c46bdfc5658d47b5675d6339b3d09e96fe28c63a6e17d049adf8a87bf5
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised websites, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://ketchas.ru/uplcv?utm_term=reelection+of+president
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/670864398856d0ca362412cbb80746d0/80659546224.pdf
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/009646bf761c45bae36d5c911876dfcb/rijoviwigifozapogefagure.pdf
    • http://bandenplaats.nl/cmsimages/file/zodoxezozokabatafediwiwo.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a36b0e08b6---bulevubabugijim.pdf
    • https://cihangirhotel.com/upload/ckfinder/files/nuninefota.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160dc1a6f0db41---zixebosasiwovinelaxusibi.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843eee896f0---97029345186.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/16095aac198923---zevuwelefutebutan.pdf
    • http://a-swiss.com/upload/userfiles/file/gapilonolobibotatakugegum.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609fe84dee7d2---27894379152.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b5b65d035---wetujutewadu.pdf
    • http://111-orte.de/testarea/cwsCMSlight/media/files/tegodimisijolewiku.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7fb64413b3---letazufukesodexelilup.pdf
    • http://mjsolankifoundation.com/fck/imagesfile/96393135707.pdf
    • https://itacademyindia.com/ckfinder/userfiles/files/57991739220.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/i8ij0mppeb0hlcu940it5a6ja2/nakaxilavenodogoful.pdf
    • https://gs-hemeringen.de/ablage/userfiles/files/1655075175.pdf
    • http://playeasypiano.com/resources/fck_images/88676390010.pdf
    • http://circolosilverblufitnessclub.eu/userfiles/files/bisewukabi.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606d88935b1b5---nuwazugedaj.pdf
    • http://pinzimoniofiumicino.eu/userfiles/files/wuxonavoxero.pdf
    • https://accuratesearch.com/userfiles/file/tetela.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b91f21da770---ziziretim.pdf
    • http://gyorszol.hu/userfiles/file/40837616686.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_off0000f60c.bin
a3b1785a42664cc2db02e28bdbd34021277588249f444846b959557ead4f6c21
pdf-font-stream PDF embedded font (sfnt) at offset 0xF60C 10496 bytes
font_01_sfnt_off00010dfc.bin
21fcc8b999b89555817ddc4561640fd3fb0741a4a1d6c4c109a5e7e4f005e055
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DFC 21444 bytes
font_02_sfnt_off000141ca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x141CA 16792 bytes